diff --git a/.gitignore b/.gitignore
index 9dd5fe0..a14e2ea 100755
--- a/.gitignore
+++ b/.gitignore
@@ -67,3 +67,4 @@ backend/mappings.db
 
 backend/tasks.db
 backend/logs
+backend/auth.db
diff --git a/.kilocode/workflows/read_semantic.md b/.kilocode/workflows/read_semantic.md
new file mode 100644
index 0000000..bde31a1
--- /dev/null
+++ b/.kilocode/workflows/read_semantic.md
@@ -0,0 +1,4 @@
+---
+description: USE SEMANTIC
+---
+Прочитай semantic_protocol.md. ОБЯЗАТЕЛЬНО используй его при разработке
\ No newline at end of file
diff --git a/.specify/memory/constitution.md b/.specify/memory/constitution.md
index 069ab61..63156cb 100644
--- a/.specify/memory/constitution.md
+++ b/.specify/memory/constitution.md
@@ -1,8 +1,8 @@
 <!--
 SYNC IMPACT REPORT
-Version: 1.8.0 (Frontend Unification)
+Version: 1.9.0 (Security & RBAC Mandate)
 Changes:
-- Added Principle VIII: Unified Frontend Experience (Mandating Design System & i18n).
+- Added Principle IX: Security & Access Control (Mandating granular permissions for plugins).
 Templates Status:
 - .specify/templates/plan-template.md: ✅ Aligned.
 - .specify/templates/spec-template.md: ✅ Aligned.
@@ -41,6 +41,11 @@ To ensure a consistent and accessible user experience, all frontend implementati
 - **Component Reusability**: All UI elements MUST utilize the standardized Svelte component library (`src/lib/ui`) and centralized design tokens. Ad-hoc styling and hardcoded values are prohibited.
 - **Internationalization (i18n)**: All user-facing text MUST be extracted to the translation system (`src/lib/i18n`). Hardcoded strings in the UI are prohibited.
 
+### IX. Security & Access Control
+To support the Role-Based Access Control (RBAC) system, all functional components must define explicit permissions.
+- **Granular Permissions**: Every Plugin MUST define a unique permission string (e.g., `plugin:name:execute`) required for its operation.
+- **Registration**: These permissions MUST be registered in the system database during initialization or plugin loading to ensure they are available for role assignment in the Admin UI.
+
 ## File Structure Standards
 Refer to **Section III (File Structure Standard)** in `semantic_protocol.md` for the authoritative definitions of:
 - Python Module Headers (`.py`)
@@ -68,4 +73,4 @@ This Constitution establishes the "Semantic Code Generation Protocol" as the sup
 - **Amendments**: Changes to core principles require a Constitution amendment. Changes to technical syntax require a Protocol update.
 - **Compliance**: Failure to adhere to the Protocol constitutes a build failure.
 
-**Version**: 1.8.0 | **Ratified**: 2025-12-19 | **Last Amended**: 2026-01-26
+**Version**: 1.9.0 | **Ratified**: 2025-12-19 | **Last Amended**: 2026-01-27
diff --git a/backend/backend/auth.db b/backend/backend/auth.db
new file mode 100644
index 0000000..d5a6357
Binary files /dev/null and b/backend/backend/auth.db differ
diff --git a/backend/mappings.db b/backend/mappings.db
index e2e76c4..81d343a 100644
Binary files a/backend/mappings.db and b/backend/mappings.db differ
diff --git a/backend/requirements.txt b/backend/requirements.txt
index 412351d..964e28d 100755
--- a/backend/requirements.txt
+++ b/backend/requirements.txt
@@ -25,9 +25,13 @@ keyring==25.7.0
 more-itertools==10.8.0
 pycparser==2.23
 pydantic==2.12.5
+pydantic-settings
 pydantic_core==2.41.5
 python-multipart==0.0.21
 PyYAML==6.0.3
+passlib[bcrypt]
+python-jose[cryptography]
+PyJWT
 RapidFuzz==3.14.3
 referencing==0.37.0
 requests==2.32.5
@@ -44,4 +48,6 @@ websockets==15.0.1
 pandas
 psycopg2-binary
 openpyxl
-GitPython==3.1.44
\ No newline at end of file
+GitPython==3.1.44
+itsdangerous
+email-validator
\ No newline at end of file
diff --git a/backend/src/api/auth.py b/backend/src/api/auth.py
index d7cde07..6ae24f5 100755
--- a/backend/src/api/auth.py
+++ b/backend/src/api/auth.py
@@ -1,59 +1,108 @@
-# [DEF:AuthModule:Module]
-# @SEMANTICS: auth, authentication, adfs, oauth, middleware
-# @PURPOSE: Implements ADFS authentication using Authlib for FastAPI. It provides a dependency to protect endpoints.
-# @LAYER: UI (API)
-# @RELATION: Used by API routers to protect endpoints that require authentication.
+# [DEF:backend.src.api.auth:Module]
+#
+# @SEMANTICS: api, auth, routes, login, logout
+# @PURPOSE:   Authentication API endpoints.
+# @LAYER:     API
+# @RELATION:  USES -> backend.src.services.auth_service.AuthService
+# @RELATION:  USES -> backend.src.core.database.get_auth_db
+#
+# @INVARIANT: All auth endpoints must return consistent error codes.
 
-from fastapi import Depends, HTTPException, status
-from fastapi.security import OAuth2AuthorizationCodeBearer
-from authlib.integrations.starlette_client import OAuth
-from starlette.config import Config
+# [SECTION: IMPORTS]
+from fastapi import APIRouter, Depends, HTTPException, status
+from fastapi.security import OAuth2PasswordRequestForm
+from sqlalchemy.orm import Session
+from ..core.database import get_auth_db
+from ..services.auth_service import AuthService
+from ..schemas.auth import Token, User as UserSchema
+from ..dependencies import get_current_user
+from ..core.auth.oauth import oauth
+from ..core.auth.logger import log_security_event
+from ..core.logger import belief_scope
+import starlette.requests
+# [/SECTION]
 
-# Placeholder for ADFS configuration. In a real app, this would come from a secure source.
-# Create an in-memory .env file
-from io import StringIO
-config_data = StringIO("""
-ADFS_CLIENT_ID=your-client-id
-ADFS_CLIENT_SECRET=your-client-secret
-ADFS_SERVER_METADATA_URL=https://your-adfs-server/.well-known/openid-configuration
-""")
-config = Config(config_data)
-oauth = OAuth(config)
+# [DEF:router:Variable]
+# @PURPOSE: APIRouter instance for authentication routes.
+router = APIRouter(prefix="/api/auth", tags=["auth"])
+# [/DEF:router:Variable]
 
-oauth.register(
-    name='adfs',
-    server_metadata_url=config('ADFS_SERVER_METADATA_URL'),
-    client_kwargs={'scope': 'openid profile email'}
-)
+# [DEF:login_for_access_token:Function]
+# @PURPOSE: Authenticates a user and returns a JWT access token.
+# @PRE:     form_data contains username and password.
+# @POST:    Returns a Token object on success.
+# @THROW:   HTTPException 401 if authentication fails.
+# @PARAM:   form_data (OAuth2PasswordRequestForm) - Login credentials.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  Token - The generated JWT token.
+@router.post("/login", response_model=Token)
+async def login_for_access_token(
+    form_data: OAuth2PasswordRequestForm = Depends(),
+    db: Session = Depends(get_auth_db)
+):
+    with belief_scope("api.auth.login"):
+        auth_service = AuthService(db)
+        user = auth_service.authenticate_user(form_data.username, form_data.password)
+        if not user:
+            log_security_event("LOGIN_FAILED", form_data.username, {"reason": "Invalid credentials"})
+            raise HTTPException(
+                status_code=status.HTTP_401_UNAUTHORIZED,
+                detail="Incorrect username or password",
+                headers={"WWW-Authenticate": "Bearer"},
+            )
+        log_security_event("LOGIN_SUCCESS", user.username, {"source": "LOCAL"})
+        return auth_service.create_session(user)
+# [/DEF:login_for_access_token:Function]
 
-oauth2_scheme = OAuth2AuthorizationCodeBearer(
-    authorizationUrl="https://your-adfs-server/adfs/oauth2/authorize",
-    tokenUrl="https://your-adfs-server/adfs/oauth2/token",
-)
+# [DEF:read_users_me:Function]
+# @PURPOSE: Retrieves the profile of the currently authenticated user.
+# @PRE:     Valid JWT token provided.
+# @POST:    Returns the current user's data.
+# @PARAM:   current_user (UserSchema) - The user extracted from the token.
+# @RETURN:  UserSchema - The current user profile.
+@router.get("/me", response_model=UserSchema)
+async def read_users_me(current_user: UserSchema = Depends(get_current_user)):
+    with belief_scope("api.auth.me"):
+        return current_user
+# [/DEF:read_users_me:Function]
 
-# [DEF:get_current_user:Function]
-# @PURPOSE: Dependency to get the current user from the ADFS token.
-# @PARAM: token (str) - The OAuth2 bearer token.
-# @PRE: token should be provided via Authorization header.
-# @POST: Returns user details if authenticated, else raises 401.
-# @RETURN: Dict[str, str] - User information.
-async def get_current_user(token: str = Depends(oauth2_scheme)):
-    """
-    Dependency to get the current user from the ADFS token.
-    This is a placeholder and needs to be fully implemented.
-    """
-    # In a real implementation, you would:
-    # 1. Validate the token with ADFS.
-    # 2. Fetch user information.
-    # 3. Create a user object.
-    # For now, we'll just check if a token exists.
-    if not token:
-        raise HTTPException(
-            status_code=status.HTTP_401_UNAUTHORIZED,
-            detail="Not authenticated",
-            headers={"WWW-Authenticate": "Bearer"},
-        )
-    # A real implementation would return a user object.
-    return {"placeholder_user": "user@example.com"}
-# [/DEF:get_current_user:Function]
-# [/DEF:AuthModule:Module]
\ No newline at end of file
+# [DEF:logout:Function]
+# @PURPOSE: Logs out the current user (placeholder for session revocation).
+# @PRE:     Valid JWT token provided.
+# @POST:    Returns success message.
+@router.post("/logout")
+async def logout(current_user: UserSchema = Depends(get_current_user)):
+    with belief_scope("api.auth.logout"):
+        log_security_event("LOGOUT", current_user.username)
+        # In a stateless JWT setup, client-side token deletion is primary.
+        # Server-side revocation (blacklisting) can be added here if needed.
+        return {"message": "Successfully logged out"}
+# [/DEF:logout:Function]
+
+# [DEF:login_adfs:Function]
+# @PURPOSE: Initiates the ADFS OIDC login flow.
+# @POST:    Redirects the user to ADFS.
+@router.get("/login/adfs")
+async def login_adfs(request: starlette.requests.Request):
+    with belief_scope("api.auth.login_adfs"):
+        redirect_uri = request.url_for('auth_callback_adfs')
+        return await oauth.adfs.authorize_redirect(request, str(redirect_uri))
+# [/DEF:login_adfs:Function]
+
+# [DEF:auth_callback_adfs:Function]
+# @PURPOSE: Handles the callback from ADFS after successful authentication.
+# @POST:    Provisions user JIT and returns session token.
+@router.get("/callback/adfs", name="auth_callback_adfs")
+async def auth_callback_adfs(request: starlette.requests.Request, db: Session = Depends(get_auth_db)):
+    with belief_scope("api.auth.callback_adfs"):
+        token = await oauth.adfs.authorize_access_token(request)
+        user_info = token.get('userinfo')
+        if not user_info:
+            raise HTTPException(status_code=400, detail="Failed to retrieve user info from ADFS")
+        
+        auth_service = AuthService(db)
+        user = auth_service.provision_adfs_user(user_info)
+        return auth_service.create_session(user)
+# [/DEF:auth_callback_adfs:Function]
+
+# [/DEF:backend.src.api.auth:Module]
\ No newline at end of file
diff --git a/backend/src/api/routes/__init__.py b/backend/src/api/routes/__init__.py
index 5bfe0f5..c975a3c 100755
--- a/backend/src/api/routes/__init__.py
+++ b/backend/src/api/routes/__init__.py
@@ -1 +1 @@
-from . import plugins, tasks, settings, connections, environments, mappings, migration, git, storage
+from . import plugins, tasks, settings, connections, environments, mappings, migration, git, storage, admin
diff --git a/backend/src/api/routes/admin.py b/backend/src/api/routes/admin.py
new file mode 100644
index 0000000..c623434
--- /dev/null
+++ b/backend/src/api/routes/admin.py
@@ -0,0 +1,305 @@
+# [DEF:backend.src.api.routes.admin:Module]
+#
+# @SEMANTICS: api, admin, users, roles, permissions
+# @PURPOSE:   Admin API endpoints for user and role management.
+# @LAYER:     API
+# @RELATION:  USES -> backend.src.core.auth.repository.AuthRepository
+# @RELATION:  USES -> backend.src.dependencies.has_permission
+#
+# @INVARIANT: All endpoints in this module require 'Admin' role or 'admin' scope.
+
+# [SECTION: IMPORTS]
+from typing import List
+from fastapi import APIRouter, Depends, HTTPException, status
+from sqlalchemy.orm import Session
+from ...core.database import get_auth_db
+from ...core.auth.repository import AuthRepository
+from ...core.auth.security import get_password_hash
+from ...schemas.auth import (
+    User as UserSchema, UserCreate, UserUpdate,
+    RoleSchema, RoleCreate, RoleUpdate, PermissionSchema,
+    ADGroupMappingSchema, ADGroupMappingCreate
+)
+from ...models.auth import User, Role, Permission, ADGroupMapping
+from ...dependencies import has_permission, get_current_user
+from ...core.logger import belief_scope
+# [/SECTION]
+
+# [DEF:router:Variable]
+# @PURPOSE: APIRouter instance for admin routes.
+router = APIRouter(prefix="/api/admin", tags=["admin"])
+# [/DEF:router:Variable]
+
+# [DEF:list_users:Function]
+# @PURPOSE: Lists all registered users.
+# @PRE:     Current user has 'Admin' role.
+# @POST:    Returns a list of UserSchema objects.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  List[UserSchema] - List of users.
+@router.get("/users", response_model=List[UserSchema])
+async def list_users(
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:users", "READ"))
+):
+    with belief_scope("api.admin.list_users"):
+        users = db.query(User).all()
+        return users
+# [/DEF:list_users:Function]
+
+# [DEF:create_user:Function]
+# @PURPOSE: Creates a new local user.
+# @PRE:     Current user has 'Admin' role.
+# @POST:    New user is created in the database.
+# @PARAM:   user_in (UserCreate) - New user data.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  UserSchema - The created user.
+@router.post("/users", response_model=UserSchema, status_code=status.HTTP_201_CREATED)
+async def create_user(
+    user_in: UserCreate,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:users", "WRITE"))
+):
+    with belief_scope("api.admin.create_user"):
+        repo = AuthRepository(db)
+        if repo.get_user_by_username(user_in.username):
+            raise HTTPException(status_code=400, detail="Username already exists")
+        
+        new_user = User(
+            username=user_in.username,
+            email=user_in.email,
+            password_hash=get_password_hash(user_in.password),
+            auth_source="LOCAL",
+            is_active=user_in.is_active
+        )
+        
+        for role_name in user_in.roles:
+            role = repo.get_role_by_name(role_name)
+            if role:
+                new_user.roles.append(role)
+        
+        db.add(new_user)
+        db.commit()
+        db.refresh(new_user)
+        return new_user
+# [/DEF:create_user:Function]
+
+# [DEF:update_user:Function]
+# @PURPOSE: Updates an existing user.
+@router.put("/users/{user_id}", response_model=UserSchema)
+async def update_user(
+    user_id: str,
+    user_in: UserUpdate,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:users", "WRITE"))
+):
+    with belief_scope("api.admin.update_user"):
+        repo = AuthRepository(db)
+        user = repo.get_user_by_id(user_id)
+        if not user:
+            raise HTTPException(status_code=404, detail="User not found")
+        
+        if user_in.email is not None:
+            user.email = user_in.email
+        if user_in.is_active is not None:
+            user.is_active = user_in.is_active
+        if user_in.password is not None:
+            user.password_hash = get_password_hash(user_in.password)
+        
+        if user_in.roles is not None:
+            user.roles = []
+            for role_name in user_in.roles:
+                role = repo.get_role_by_name(role_name)
+                if role:
+                    user.roles.append(role)
+        
+        db.commit()
+        db.refresh(user)
+        return user
+# [/DEF:update_user:Function]
+
+# [DEF:delete_user:Function]
+# @PURPOSE: Deletes a user.
+@router.delete("/users/{user_id}", status_code=status.HTTP_204_NO_CONTENT)
+async def delete_user(
+    user_id: str,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:users", "WRITE"))
+):
+    with belief_scope("api.admin.delete_user"):
+        repo = AuthRepository(db)
+        user = repo.get_user_by_id(user_id)
+        if not user:
+            raise HTTPException(status_code=404, detail="User not found")
+        
+        db.delete(user)
+        db.commit()
+        return None
+# [/DEF:delete_user:Function]
+
+# [DEF:list_roles:Function]
+# @PURPOSE: Lists all available roles.
+# @RETURN:  List[RoleSchema] - List of roles.
+# @RELATION: CALLS -> backend.src.models.auth.Role
+@router.get("/roles", response_model=List[RoleSchema])
+async def list_roles(
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:roles", "READ"))
+):
+    with belief_scope("api.admin.list_roles"):
+        return db.query(Role).all()
+# [/DEF:list_roles:Function]
+
+# [DEF:create_role:Function]
+# @PURPOSE: Creates a new system role with associated permissions.
+# @PRE:     Role name must be unique.
+# @POST:    New Role record is created in auth.db.
+# @PARAM:   role_in (RoleCreate) - New role data.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  RoleSchema - The created role.
+# @SIDE_EFFECT: Commits new role and associations to auth.db.
+# @RELATION: CALLS -> backend.src.core.auth.repository.AuthRepository.get_permission_by_id
+@router.post("/roles", response_model=RoleSchema, status_code=status.HTTP_201_CREATED)
+async def create_role(
+    role_in: RoleCreate,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:roles", "WRITE"))
+):
+    with belief_scope("api.admin.create_role"):
+        if db.query(Role).filter(Role.name == role_in.name).first():
+            raise HTTPException(status_code=400, detail="Role already exists")
+        
+        new_role = Role(name=role_in.name, description=role_in.description)
+        repo = AuthRepository(db)
+        
+        for perm_id_or_str in role_in.permissions:
+            perm = repo.get_permission_by_id(perm_id_or_str)
+            if not perm and ":" in perm_id_or_str:
+                res, act = perm_id_or_str.split(":", 1)
+                perm = repo.get_permission_by_resource_action(res, act)
+            
+            if perm:
+                new_role.permissions.append(perm)
+        
+        db.add(new_role)
+        db.commit()
+        db.refresh(new_role)
+        return new_role
+# [/DEF:create_role:Function]
+
+# [DEF:update_role:Function]
+# @PURPOSE: Updates an existing role's metadata and permissions.
+# @PRE:     role_id must be a valid existing role UUID.
+# @POST:    Role record is updated in auth.db.
+# @PARAM:   role_id (str) - Target role identifier.
+# @PARAM:   role_in (RoleUpdate) - Updated role data.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  RoleSchema - The updated role.
+# @SIDE_EFFECT: Commits updates to auth.db.
+# @RELATION: CALLS -> backend.src.core.auth.repository.AuthRepository.get_role_by_id
+@router.put("/roles/{role_id}", response_model=RoleSchema)
+async def update_role(
+    role_id: str,
+    role_in: RoleUpdate,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:roles", "WRITE"))
+):
+    with belief_scope("api.admin.update_role"):
+        repo = AuthRepository(db)
+        role = repo.get_role_by_id(role_id)
+        if not role:
+            raise HTTPException(status_code=404, detail="Role not found")
+        
+        if role_in.name is not None:
+            role.name = role_in.name
+        if role_in.description is not None:
+            role.description = role_in.description
+        
+        if role_in.permissions is not None:
+            role.permissions = []
+            for perm_id_or_str in role_in.permissions:
+                perm = repo.get_permission_by_id(perm_id_or_str)
+                if not perm and ":" in perm_id_or_str:
+                    res, act = perm_id_or_str.split(":", 1)
+                    perm = repo.get_permission_by_resource_action(res, act)
+                
+                if perm:
+                    role.permissions.append(perm)
+        
+        db.commit()
+        db.refresh(role)
+        return role
+# [/DEF:update_role:Function]
+
+# [DEF:delete_role:Function]
+# @PURPOSE: Removes a role from the system.
+# @PRE:     role_id must be a valid existing role UUID.
+# @POST:    Role record is removed from auth.db.
+# @PARAM:   role_id (str) - Target role identifier.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  None
+# @SIDE_EFFECT: Deletes record from auth.db and commits.
+# @RELATION: CALLS -> backend.src.core.auth.repository.AuthRepository.get_role_by_id
+@router.delete("/roles/{role_id}", status_code=status.HTTP_204_NO_CONTENT)
+async def delete_role(
+    role_id: str,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:roles", "WRITE"))
+):
+    with belief_scope("api.admin.delete_role"):
+        repo = AuthRepository(db)
+        role = repo.get_role_by_id(role_id)
+        if not role:
+            raise HTTPException(status_code=404, detail="Role not found")
+        
+        db.delete(role)
+        db.commit()
+        return None
+# [/DEF:delete_role:Function]
+
+# [DEF:list_permissions:Function]
+# @PURPOSE: Lists all available system permissions for assignment.
+# @POST:    Returns a list of all PermissionSchema objects.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  List[PermissionSchema] - List of permissions.
+# @RELATION: CALLS -> backend.src.core.auth.repository.AuthRepository.list_permissions
+@router.get("/permissions", response_model=List[PermissionSchema])
+async def list_permissions(
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:roles", "READ"))
+):
+    with belief_scope("api.admin.list_permissions"):
+        repo = AuthRepository(db)
+        return repo.list_permissions()
+# [/DEF:list_permissions:Function]
+
+# [DEF:list_ad_mappings:Function]
+# @PURPOSE: Lists all AD Group to Role mappings.
+@router.get("/ad-mappings", response_model=List[ADGroupMappingSchema])
+async def list_ad_mappings(
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:settings", "READ"))
+):
+    with belief_scope("api.admin.list_ad_mappings"):
+        return db.query(ADGroupMapping).all()
+# [/DEF:list_ad_mappings:Function]
+
+# [DEF:create_ad_mapping:Function]
+# @PURPOSE: Creates a new AD Group mapping.
+@router.post("/ad-mappings", response_model=ADGroupMappingSchema)
+async def create_ad_mapping(
+    mapping_in: ADGroupMappingCreate,
+    db: Session = Depends(get_auth_db),
+    _ = Depends(has_permission("admin:settings", "WRITE"))
+):
+    with belief_scope("api.admin.create_ad_mapping"):
+        new_mapping = ADGroupMapping(
+            ad_group=mapping_in.ad_group,
+            role_id=mapping_in.role_id
+        )
+        db.add(new_mapping)
+        db.commit()
+        db.refresh(new_mapping)
+        return new_mapping
+# [/DEF:create_ad_mapping:Function]
+
+# [/DEF:backend.src.api.routes.admin:Module]
\ No newline at end of file
diff --git a/backend/src/api/routes/settings.py b/backend/src/api/routes/settings.py
index 33a4cdf..6d7d751 100755
--- a/backend/src/api/routes/settings.py
+++ b/backend/src/api/routes/settings.py
@@ -14,7 +14,7 @@ from fastapi import APIRouter, Depends, HTTPException
 from typing import List
 from ...core.config_models import AppConfig, Environment, GlobalSettings
 from ...models.storage import StorageConfig
-from ...dependencies import get_config_manager
+from ...dependencies import get_config_manager, has_permission
 from ...core.config_manager import ConfigManager
 from ...core.logger import logger, belief_scope
 from ...core.superset_client import SupersetClient
@@ -29,7 +29,10 @@ router = APIRouter()
 # @POST:    Returns masked AppConfig.
 # @RETURN: AppConfig - The current configuration.
 @router.get("", response_model=AppConfig)
-async def get_settings(config_manager: ConfigManager = Depends(get_config_manager)):
+async def get_settings(
+    config_manager: ConfigManager = Depends(get_config_manager),
+    _ = Depends(has_permission("settings", "READ"))
+):
     with belief_scope("get_settings"):
         logger.info("[get_settings][Entry] Fetching all settings")
     config = config_manager.get_config().copy(deep=True)
@@ -49,7 +52,8 @@ async def get_settings(config_manager: ConfigManager = Depends(get_config_manage
 @router.patch("/global", response_model=GlobalSettings)
 async def update_global_settings(
     settings: GlobalSettings,
-    config_manager: ConfigManager = Depends(get_config_manager)
+    config_manager: ConfigManager = Depends(get_config_manager),
+    _ = Depends(has_permission("settings", "WRITE"))
 ):
     with belief_scope("update_global_settings"):
         logger.info("[update_global_settings][Entry] Updating global settings")
@@ -62,7 +66,10 @@ async def update_global_settings(
 # @PURPOSE: Retrieves storage-specific settings.
 # @RETURN: StorageConfig - The storage configuration.
 @router.get("/storage", response_model=StorageConfig)
-async def get_storage_settings(config_manager: ConfigManager = Depends(get_config_manager)):
+async def get_storage_settings(
+    config_manager: ConfigManager = Depends(get_config_manager),
+    _ = Depends(has_permission("settings", "READ"))
+):
     with belief_scope("get_storage_settings"):
         return config_manager.get_config().settings.storage
 # [/DEF:get_storage_settings:Function]
@@ -73,7 +80,11 @@ async def get_storage_settings(config_manager: ConfigManager = Depends(get_confi
 # @POST: Storage settings are updated and saved.
 # @RETURN: StorageConfig - The updated storage settings.
 @router.put("/storage", response_model=StorageConfig)
-async def update_storage_settings(storage: StorageConfig, config_manager: ConfigManager = Depends(get_config_manager)):
+async def update_storage_settings(
+    storage: StorageConfig,
+    config_manager: ConfigManager = Depends(get_config_manager),
+    _ = Depends(has_permission("settings", "WRITE"))
+):
     with belief_scope("update_storage_settings"):
         is_valid, message = config_manager.validate_path(storage.root_path)
         if not is_valid:
@@ -91,7 +102,10 @@ async def update_storage_settings(storage: StorageConfig, config_manager: Config
 # @POST:    Returns list of environments.
 # @RETURN: List[Environment] - List of environments.
 @router.get("/environments", response_model=List[Environment])
-async def get_environments(config_manager: ConfigManager = Depends(get_config_manager)):
+async def get_environments(
+    config_manager: ConfigManager = Depends(get_config_manager),
+    _ = Depends(has_permission("settings", "READ"))
+):
     with belief_scope("get_environments"):
         logger.info("[get_environments][Entry] Fetching environments")
     return config_manager.get_environments()
@@ -106,7 +120,8 @@ async def get_environments(config_manager: ConfigManager = Depends(get_config_ma
 @router.post("/environments", response_model=Environment)
 async def add_environment(
     env: Environment,
-    config_manager: ConfigManager = Depends(get_config_manager)
+    config_manager: ConfigManager = Depends(get_config_manager),
+    _ = Depends(has_permission("settings", "WRITE"))
 ):
     with belief_scope("add_environment"):
         logger.info(f"[add_environment][Entry] Adding environment {env.id}")
diff --git a/backend/src/api/routes/tasks.py b/backend/src/api/routes/tasks.py
index 006c76a..a28096f 100755
--- a/backend/src/api/routes/tasks.py
+++ b/backend/src/api/routes/tasks.py
@@ -9,7 +9,7 @@ from pydantic import BaseModel
 from ...core.logger import belief_scope
 
 from ...core.task_manager import TaskManager, Task, TaskStatus, LogEntry
-from ...dependencies import get_task_manager
+from ...dependencies import get_task_manager, has_permission
 
 router = APIRouter()
 
@@ -33,7 +33,8 @@ class ResumeTaskRequest(BaseModel):
 # @RETURN: Task - The created task instance.
 async def create_task(
     request: CreateTaskRequest,
-    task_manager: TaskManager = Depends(get_task_manager)
+    task_manager: TaskManager = Depends(get_task_manager),
+    _ = Depends(lambda req: has_permission(f"plugin:{req.plugin_id}", "EXECUTE"))
 ):
     """
     Create and start a new task for a given plugin.
diff --git a/backend/src/app.py b/backend/src/app.py
index b31f50d..89f2ce7 100755
--- a/backend/src/app.py
+++ b/backend/src/app.py
@@ -10,6 +10,7 @@ from pathlib import Path
 project_root = Path(__file__).resolve().parent.parent.parent
 
 from fastapi import FastAPI, WebSocket, WebSocketDisconnect, Depends, Request, HTTPException
+from starlette.middleware.sessions import SessionMiddleware
 from fastapi.middleware.cors import CORSMiddleware
 from fastapi.staticfiles import StaticFiles
 from fastapi.responses import FileResponse
@@ -18,7 +19,8 @@ import os
 
 from .dependencies import get_task_manager, get_scheduler_service
 from .core.logger import logger, belief_scope
-from .api.routes import plugins, tasks, settings, environments, mappings, migration, connections, git, storage
+from .api.routes import plugins, tasks, settings, environments, mappings, migration, connections, git, storage, admin
+from .api import auth
 from .core.database import init_db
 
 # [DEF:App:Global]
@@ -55,6 +57,10 @@ async def shutdown_event():
     scheduler.stop()
 # [/DEF:shutdown_event:Function]
 
+# Configure Session Middleware (required by Authlib for OAuth2 flow)
+from .core.auth.config import auth_config
+app.add_middleware(SessionMiddleware, secret_key=auth_config.SECRET_KEY)
+
 # Configure CORS
 app.add_middleware(
     CORSMiddleware,
@@ -81,6 +87,8 @@ async def log_requests(request: Request, call_next):
 # [/DEF:log_requests:Function]
 
 # Include API routes
+app.include_router(auth.router)
+app.include_router(admin.router)
 app.include_router(plugins.router, prefix="/api/plugins", tags=["Plugins"])
 app.include_router(tasks.router, prefix="/api/tasks", tags=["Tasks"])
 app.include_router(settings.router, prefix="/api/settings", tags=["Settings"])
diff --git a/backend/src/core/auth/config.py b/backend/src/core/auth/config.py
new file mode 100644
index 0000000..e424ba7
--- /dev/null
+++ b/backend/src/core/auth/config.py
@@ -0,0 +1,45 @@
+# [DEF:backend.src.core.auth.config:Module]
+#
+# @SEMANTICS: auth, config, settings, jwt, adfs
+# @PURPOSE:   Centralized configuration for authentication and authorization.
+# @LAYER:     Core
+# @RELATION:  DEPENDS_ON -> pydantic
+#
+# @INVARIANT: All sensitive configuration must have defaults or be loaded from environment.
+
+# [SECTION: IMPORTS]
+from pydantic import Field
+from pydantic_settings import BaseSettings
+import os
+# [/SECTION]
+
+# [DEF:AuthConfig:Class]
+# @PURPOSE: Holds authentication-related settings.
+# @PRE:     Environment variables may be provided via .env file.
+# @POST:    Returns a configuration object with validated settings.
+class AuthConfig(BaseSettings):
+    # JWT Settings
+    SECRET_KEY: str = Field(default="super-secret-key-change-in-production", env="AUTH_SECRET_KEY")
+    ALGORITHM: str = "HS256"
+    ACCESS_TOKEN_EXPIRE_MINUTES: int = 30
+    REFRESH_TOKEN_EXPIRE_DAYS: int = 7
+
+    # Database Settings
+    AUTH_DATABASE_URL: str = Field(default="sqlite:///./backend/auth.db", env="AUTH_DATABASE_URL")
+
+    # ADFS Settings
+    ADFS_CLIENT_ID: str = Field(default="", env="ADFS_CLIENT_ID")
+    ADFS_CLIENT_SECRET: str = Field(default="", env="ADFS_CLIENT_SECRET")
+    ADFS_METADATA_URL: str = Field(default="", env="ADFS_METADATA_URL")
+    
+    class Config:
+        env_file = ".env"
+        extra = "ignore"
+# [/DEF:AuthConfig:Class]
+
+# [DEF:auth_config:Variable]
+# @PURPOSE: Singleton instance of AuthConfig.
+auth_config = AuthConfig()
+# [/DEF:auth_config:Variable]
+
+# [/DEF:backend.src.core.auth.config:Module]
\ No newline at end of file
diff --git a/backend/src/core/auth/jwt.py b/backend/src/core/auth/jwt.py
new file mode 100644
index 0000000..aecb321
--- /dev/null
+++ b/backend/src/core/auth/jwt.py
@@ -0,0 +1,54 @@
+# [DEF:backend.src.core.auth.jwt:Module]
+#
+# @SEMANTICS: jwt, token, session, auth
+# @PURPOSE:   JWT token generation and validation logic.
+# @LAYER:     Core
+# @RELATION:  DEPENDS_ON -> jose
+# @RELATION:  USES -> backend.src.core.auth.config.auth_config
+#
+# @INVARIANT: Tokens must include expiration time and user identifier.
+
+# [SECTION: IMPORTS]
+from datetime import datetime, timedelta
+from typing import Optional, List
+from jose import JWTError, jwt
+from .config import auth_config
+from ..logger import belief_scope
+# [/SECTION]
+
+# [DEF:create_access_token:Function]
+# @PURPOSE: Generates a new JWT access token.
+# @PRE:     data dict contains 'sub' (user_id) and optional 'scopes' (roles).
+# @POST:    Returns a signed JWT string.
+#
+# @PARAM:   data (dict) - Payload data for the token.
+# @PARAM:   expires_delta (Optional[timedelta]) - Custom expiration time.
+# @RETURN:  str - The encoded JWT.
+def create_access_token(data: dict, expires_delta: Optional[timedelta] = None) -> str:
+    with belief_scope("create_access_token"):
+        to_encode = data.copy()
+        if expires_delta:
+            expire = datetime.utcnow() + expires_delta
+        else:
+            expire = datetime.utcnow() + timedelta(minutes=auth_config.ACCESS_TOKEN_EXPIRE_MINUTES)
+        
+        to_encode.update({"exp": expire})
+        encoded_jwt = jwt.encode(to_encode, auth_config.SECRET_KEY, algorithm=auth_config.ALGORITHM)
+        return encoded_jwt
+# [/DEF:create_access_token:Function]
+
+# [DEF:decode_token:Function]
+# @PURPOSE: Decodes and validates a JWT token.
+# @PRE:     token is a signed JWT string.
+# @POST:    Returns the decoded payload if valid.
+#
+# @PARAM:   token (str) - The JWT to decode.
+# @RETURN:  dict - The decoded payload.
+# @THROW:   jose.JWTError - If token is invalid or expired.
+def decode_token(token: str) -> dict:
+    with belief_scope("decode_token"):
+        payload = jwt.decode(token, auth_config.SECRET_KEY, algorithms=[auth_config.ALGORITHM])
+        return payload
+# [/DEF:decode_token:Function]
+
+# [/DEF:backend.src.core.auth.jwt:Module]
\ No newline at end of file
diff --git a/backend/src/core/auth/logger.py b/backend/src/core/auth/logger.py
new file mode 100644
index 0000000..e40a58a
--- /dev/null
+++ b/backend/src/core/auth/logger.py
@@ -0,0 +1,31 @@
+# [DEF:backend.src.core.auth.logger:Module]
+#
+# @SEMANTICS: auth, logger, audit, security
+# @PURPOSE:   Audit logging for security-related events.
+# @LAYER:     Core
+# @RELATION:  USES -> backend.src.core.logger.belief_scope
+#
+# @INVARIANT: Must not log sensitive data like passwords or full tokens.
+
+# [SECTION: IMPORTS]
+from ..logger import logger, belief_scope
+from datetime import datetime
+# [/SECTION]
+
+# [DEF:log_security_event:Function]
+# @PURPOSE: Logs a security-related event for audit trails.
+# @PRE:     event_type and username are strings.
+# @POST:    Security event is written to the application log.
+# @PARAM:   event_type (str) - Type of event (e.g., LOGIN_SUCCESS, PERMISSION_DENIED).
+# @PARAM:   username (str) - The user involved in the event.
+# @PARAM:   details (dict) - Additional non-sensitive metadata.
+def log_security_event(event_type: str, username: str, details: dict = None):
+    with belief_scope("log_security_event", f"{event_type}:{username}"):
+        timestamp = datetime.utcnow().isoformat()
+        msg = f"[AUDIT][{timestamp}][{event_type}] User: {username}"
+        if details:
+            msg += f" Details: {details}"
+        logger.info(msg)
+# [/DEF:log_security_event:Function]
+
+# [/DEF:backend.src.core.auth.logger:Module]
\ No newline at end of file
diff --git a/backend/src/core/auth/oauth.py b/backend/src/core/auth/oauth.py
new file mode 100644
index 0000000..851a517
--- /dev/null
+++ b/backend/src/core/auth/oauth.py
@@ -0,0 +1,41 @@
+# [DEF:backend.src.core.auth.oauth:Module]
+#
+# @SEMANTICS: auth, oauth, oidc, adfs
+# @PURPOSE:   ADFS OIDC configuration and client using Authlib.
+# @LAYER:     Core
+# @RELATION:  DEPENDS_ON -> authlib
+# @RELATION:  USES -> backend.src.core.auth.config.auth_config
+#
+# @INVARIANT: Must use secure OIDC flows.
+
+# [SECTION: IMPORTS]
+from authlib.integrations.starlette_client import OAuth
+from .config import auth_config
+# [/SECTION]
+
+# [DEF:oauth:Variable]
+# @PURPOSE: Global Authlib OAuth registry.
+oauth = OAuth()
+# [/DEF:oauth:Variable]
+
+# [DEF:register_adfs:Function]
+# @PURPOSE: Registers the ADFS OIDC client.
+# @PRE:     ADFS configuration is provided in auth_config.
+# @POST:    ADFS client is registered in oauth registry.
+def register_adfs():
+    if auth_config.ADFS_CLIENT_ID:
+        oauth.register(
+            name='adfs',
+            client_id=auth_config.ADFS_CLIENT_ID,
+            client_secret=auth_config.ADFS_CLIENT_SECRET,
+            server_metadata_url=auth_config.ADFS_METADATA_URL,
+            client_kwargs={
+                'scope': 'openid email profile groups'
+            }
+        )
+# [/DEF:register_adfs:Function]
+
+# Initial registration
+register_adfs()
+
+# [/DEF:backend.src.core.auth.oauth:Module]
\ No newline at end of file
diff --git a/backend/src/core/auth/repository.py b/backend/src/core/auth/repository.py
new file mode 100644
index 0000000..460a27f
--- /dev/null
+++ b/backend/src/core/auth/repository.py
@@ -0,0 +1,123 @@
+# [DEF:backend.src.core.auth.repository:Module]
+#
+# @SEMANTICS: auth, repository, database, user, role
+# @PURPOSE:   Data access layer for authentication-related entities.
+# @LAYER:     Core
+# @RELATION:  DEPENDS_ON -> sqlalchemy
+# @RELATION:  USES -> backend.src.models.auth
+#
+# @INVARIANT: All database operations must be performed within a session.
+
+# [SECTION: IMPORTS]
+from typing import Optional, List
+from sqlalchemy.orm import Session
+from ...models.auth import User, Role, Permission, ADGroupMapping
+from ..logger import belief_scope
+# [/SECTION]
+
+# [DEF:AuthRepository:Class]
+# @PURPOSE: Encapsulates database operations for authentication.
+class AuthRepository:
+    # [DEF:__init__:Function]
+    # @PURPOSE: Initializes the repository with a database session.
+    # @PARAM:   db (Session) - SQLAlchemy session.
+    def __init__(self, db: Session):
+        self.db = db
+    # [/DEF:__init__:Function]
+
+    # [DEF:get_user_by_username:Function]
+    # @PURPOSE: Retrieves a user by their username.
+    # @PRE:     username is a string.
+    # @POST:    Returns User object if found, else None.
+    # @PARAM:   username (str) - The username to search for.
+    # @RETURN:  Optional[User] - The found user or None.
+    def get_user_by_username(self, username: str) -> Optional[User]:
+        with belief_scope("AuthRepository.get_user_by_username"):
+            return self.db.query(User).filter(User.username == username).first()
+    # [/DEF:get_user_by_username:Function]
+
+    # [DEF:get_user_by_id:Function]
+    # @PURPOSE: Retrieves a user by their unique ID.
+    # @PRE:     user_id is a valid UUID string.
+    # @POST:    Returns User object if found, else None.
+    # @PARAM:   user_id (str) - The user's unique identifier.
+    # @RETURN:  Optional[User] - The found user or None.
+    def get_user_by_id(self, user_id: str) -> Optional[User]:
+        with belief_scope("AuthRepository.get_user_by_id"):
+            return self.db.query(User).filter(User.id == user_id).first()
+    # [/DEF:get_user_by_id:Function]
+
+    # [DEF:get_role_by_name:Function]
+    # @PURPOSE: Retrieves a role by its name.
+    # @PRE:     name is a string.
+    # @POST:    Returns Role object if found, else None.
+    # @PARAM:   name (str) - The role name to search for.
+    # @RETURN:  Optional[Role] - The found role or None.
+    def get_role_by_name(self, name: str) -> Optional[Role]:
+        with belief_scope("AuthRepository.get_role_by_name"):
+            return self.db.query(Role).filter(Role.name == name).first()
+    # [/DEF:get_role_by_name:Function]
+
+    # [DEF:update_last_login:Function]
+    # @PURPOSE: Updates the last_login timestamp for a user.
+    # @PRE:     user object is a valid User instance.
+    # @POST:    User's last_login is updated in the database.
+    # @SIDE_EFFECT: Commits the transaction.
+    # @PARAM:   user (User) - The user to update.
+    def update_last_login(self, user: User):
+        with belief_scope("AuthRepository.update_last_login"):
+            from datetime import datetime
+            user.last_login = datetime.utcnow()
+            self.db.add(user)
+            self.db.commit()
+    # [/DEF:update_last_login:Function]
+
+    # [DEF:get_role_by_id:Function]
+    # @PURPOSE: Retrieves a role by its unique ID.
+    # @PRE:     role_id is a string.
+    # @POST:    Returns Role object if found, else None.
+    # @PARAM:   role_id (str) - The role's unique identifier.
+    # @RETURN:  Optional[Role] - The found role or None.
+    def get_role_by_id(self, role_id: str) -> Optional[Role]:
+        with belief_scope("AuthRepository.get_role_by_id"):
+            return self.db.query(Role).filter(Role.id == role_id).first()
+    # [/DEF:get_role_by_id:Function]
+
+    # [DEF:get_permission_by_id:Function]
+    # @PURPOSE: Retrieves a permission by its unique ID.
+    # @PRE:     perm_id is a string.
+    # @POST:    Returns Permission object if found, else None.
+    # @PARAM:   perm_id (str) - The permission's unique identifier.
+    # @RETURN:  Optional[Permission] - The found permission or None.
+    def get_permission_by_id(self, perm_id: str) -> Optional[Permission]:
+        with belief_scope("AuthRepository.get_permission_by_id"):
+            return self.db.query(Permission).filter(Permission.id == perm_id).first()
+    # [/DEF:get_permission_by_id:Function]
+
+    # [DEF:get_permission_by_resource_action:Function]
+    # @PURPOSE: Retrieves a permission by resource and action.
+    # @PRE:     resource and action are strings.
+    # @POST:    Returns Permission object if found, else None.
+    # @PARAM:   resource (str) - The resource name.
+    # @PARAM:   action (str) - The action name.
+    # @RETURN:  Optional[Permission] - The found permission or None.
+    def get_permission_by_resource_action(self, resource: str, action: str) -> Optional[Permission]:
+        with belief_scope("AuthRepository.get_permission_by_resource_action"):
+            return self.db.query(Permission).filter(
+                Permission.resource == resource,
+                Permission.action == action
+            ).first()
+    # [/DEF:get_permission_by_resource_action:Function]
+
+    # [DEF:list_permissions:Function]
+    # @PURPOSE: Lists all available permissions.
+    # @POST:    Returns a list of all Permission objects.
+    # @RETURN:  List[Permission] - List of permissions.
+    def list_permissions(self) -> List[Permission]:
+        with belief_scope("AuthRepository.list_permissions"):
+            return self.db.query(Permission).all()
+    # [/DEF:list_permissions:Function]
+
+# [/DEF:AuthRepository:Class]
+
+# [/DEF:backend.src.core.auth.repository:Module]
\ No newline at end of file
diff --git a/backend/src/core/auth/security.py b/backend/src/core/auth/security.py
new file mode 100644
index 0000000..408040a
--- /dev/null
+++ b/backend/src/core/auth/security.py
@@ -0,0 +1,42 @@
+# [DEF:backend.src.core.auth.security:Module]
+#
+# @SEMANTICS: security, password, hashing, bcrypt
+# @PURPOSE:   Utility for password hashing and verification using Passlib.
+# @LAYER:     Core
+# @RELATION:  DEPENDS_ON -> passlib
+#
+# @INVARIANT: Uses bcrypt for hashing with standard work factor.
+
+# [SECTION: IMPORTS]
+from passlib.context import CryptContext
+# [/SECTION]
+
+# [DEF:pwd_context:Variable]
+# @PURPOSE: Passlib CryptContext for password management.
+pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
+# [/DEF:pwd_context:Variable]
+
+# [DEF:verify_password:Function]
+# @PURPOSE: Verifies a plain password against a hashed password.
+# @PRE:     plain_password is a string, hashed_password is a bcrypt hash.
+# @POST:    Returns True if password matches, False otherwise.
+#
+# @PARAM:   plain_password (str) - The unhashed password.
+# @PARAM:   hashed_password (str) - The stored hash.
+# @RETURN:  bool - Verification result.
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    return pwd_context.verify(plain_password, hashed_password)
+# [/DEF:verify_password:Function]
+
+# [DEF:get_password_hash:Function]
+# @PURPOSE: Generates a bcrypt hash for a plain password.
+# @PRE:     password is a string.
+# @POST:    Returns a secure bcrypt hash string.
+#
+# @PARAM:   password (str) - The password to hash.
+# @RETURN:  str - The generated hash.
+def get_password_hash(password: str) -> str:
+    return pwd_context.hash(password)
+# [/DEF:get_password_hash:Function]
+
+# [/DEF:backend.src.core.auth.security:Module]
\ No newline at end of file
diff --git a/backend/src/core/database.py b/backend/src/core/database.py
index 816769e..27f841d 100644
--- a/backend/src/core/database.py
+++ b/backend/src/core/database.py
@@ -5,6 +5,7 @@
 # @LAYER:     Core
 # @RELATION:  DEPENDS_ON -> sqlalchemy
 # @RELATION:  USES -> backend.src.models.mapping
+# @RELATION:  USES -> backend.src.core.auth.config
 #
 # @INVARIANT: A single engine instance is used for the entire application.
 
@@ -16,44 +17,70 @@ from ..models.mapping import Base
 from ..models.task import TaskRecord
 from ..models.connection import ConnectionConfig
 from ..models.git import GitServerConfig, GitRepository, DeploymentEnvironment
+from ..models.auth import User, Role, Permission, ADGroupMapping
 from .logger import belief_scope
+from .auth.config import auth_config
 import os
 # [/SECTION]
 
 # [DEF:DATABASE_URL:Constant]
+# @PURPOSE: URL for the main mappings database.
 DATABASE_URL = os.getenv("DATABASE_URL", "sqlite:///./mappings.db")
 # [/DEF:DATABASE_URL:Constant]
 
 # [DEF:TASKS_DATABASE_URL:Constant]
+# @PURPOSE: URL for the tasks execution database.
 TASKS_DATABASE_URL = os.getenv("TASKS_DATABASE_URL", "sqlite:///./tasks.db")
 # [/DEF:TASKS_DATABASE_URL:Constant]
 
+# [DEF:AUTH_DATABASE_URL:Constant]
+# @PURPOSE: URL for the authentication database.
+AUTH_DATABASE_URL = auth_config.AUTH_DATABASE_URL
+# [/DEF:AUTH_DATABASE_URL:Constant]
+
 # [DEF:engine:Variable]
+# @PURPOSE: SQLAlchemy engine for mappings database.
 engine = create_engine(DATABASE_URL, connect_args={"check_same_thread": False})
 # [/DEF:engine:Variable]
 
 # [DEF:tasks_engine:Variable]
+# @PURPOSE: SQLAlchemy engine for tasks database.
 tasks_engine = create_engine(TASKS_DATABASE_URL, connect_args={"check_same_thread": False})
 # [/DEF:tasks_engine:Variable]
 
+# [DEF:auth_engine:Variable]
+# @PURPOSE: SQLAlchemy engine for authentication database.
+auth_engine = create_engine(AUTH_DATABASE_URL, connect_args={"check_same_thread": False})
+# [/DEF:auth_engine:Variable]
+
 # [DEF:SessionLocal:Class]
 # @PURPOSE: A session factory for the main mappings database.
+# @PRE: engine is initialized.
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
 # [/DEF:SessionLocal:Class]
 
 # [DEF:TasksSessionLocal:Class]
 # @PURPOSE: A session factory for the tasks execution database.
+# @PRE: tasks_engine is initialized.
 TasksSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=tasks_engine)
 # [/DEF:TasksSessionLocal:Class]
 
+# [DEF:AuthSessionLocal:Class]
+# @PURPOSE: A session factory for the authentication database.
+# @PRE: auth_engine is initialized.
+AuthSessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=auth_engine)
+# [/DEF:AuthSessionLocal:Class]
+
 # [DEF:init_db:Function]
 # @PURPOSE: Initializes the database by creating all tables.
-# @PRE: engine and tasks_engine are initialized.
-# @POST: Database tables created.
+# @PRE: engine, tasks_engine and auth_engine are initialized.
+# @POST: Database tables created in all databases.
+# @SIDE_EFFECT: Creates physical database files if they don't exist.
 def init_db():
     with belief_scope("init_db"):
         Base.metadata.create_all(bind=engine)
         Base.metadata.create_all(bind=tasks_engine)
+        Base.metadata.create_all(bind=auth_engine)
 # [/DEF:init_db:Function]
 
 # [DEF:get_db:Function]
@@ -84,4 +111,18 @@ def get_tasks_db():
             db.close()
 # [/DEF:get_tasks_db:Function]
 
+# [DEF:get_auth_db:Function]
+# @PURPOSE: Dependency for getting an authentication database session.
+# @PRE: AuthSessionLocal is initialized.
+# @POST:    Session is closed after use.
+# @RETURN:  Generator[Session, None, None]
+def get_auth_db():
+    with belief_scope("get_auth_db"):
+        db = AuthSessionLocal()
+        try:
+            yield db
+        finally:
+            db.close()
+# [/DEF:get_auth_db:Function]
+
 # [/DEF:backend.src.core.database:Module]
diff --git a/backend/src/core/plugin_base.py b/backend/src/core/plugin_base.py
index 82e19fc..bda3565 100755
--- a/backend/src/core/plugin_base.py
+++ b/backend/src/core/plugin_base.py
@@ -68,6 +68,18 @@ class PluginBase(ABC):
             pass
     # [/DEF:version:Function]
 
+    @property
+    # [DEF:required_permission:Function]
+    # @PURPOSE: Returns the required permission string to execute this plugin.
+    # @PRE: Plugin instance exists.
+    # @POST: Returns string permission.
+    # @RETURN: str - Required permission (e.g., "plugin:backup:execute").
+    def required_permission(self) -> str:
+        """The permission string required to execute this plugin."""
+        with belief_scope("required_permission"):
+            return f"plugin:{self.id}:execute"
+    # [/DEF:required_permission:Function]
+
     @property
     # [DEF:ui_route:Function]
     # @PURPOSE: Returns the frontend route for the plugin's UI, if applicable.
diff --git a/backend/src/dependencies.py b/backend/src/dependencies.py
index ee4ead1..bc206a0 100755
--- a/backend/src/dependencies.py
+++ b/backend/src/dependencies.py
@@ -1,16 +1,23 @@
 # [DEF:Dependencies:Module]
-# @SEMANTICS: dependency, injection, singleton, factory
+# @SEMANTICS: dependency, injection, singleton, factory, auth, jwt
 # @PURPOSE: Manages the creation and provision of shared application dependencies, such as the PluginLoader and TaskManager, to avoid circular imports.
 # @LAYER: Core
 # @RELATION: Used by the main app and API routers to get access to shared instances.
 
 from pathlib import Path
+from typing import Optional
+from fastapi import Depends, HTTPException, status
+from fastapi.security import OAuth2PasswordBearer
+from jose import JWTError
 from .core.plugin_loader import PluginLoader
 from .core.task_manager import TaskManager
 from .core.config_manager import ConfigManager
 from .core.scheduler import SchedulerService
-from .core.database import init_db
+from .core.database import init_db, get_auth_db
 from .core.logger import logger, belief_scope
+from .core.auth.jwt import decode_token
+from .core.auth.repository import AuthRepository
+from .models.auth import User
 
 # Initialize singletons
 # Use absolute path relative to this file to ensure plugins are found regardless of CWD
@@ -77,4 +84,70 @@ def get_scheduler_service() -> SchedulerService:
         return scheduler_service
 # [/DEF:get_scheduler_service:Function]
 
+# [DEF:oauth2_scheme:Variable]
+# @PURPOSE: OAuth2 password bearer scheme for token extraction.
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="api/auth/login")
+# [/DEF:oauth2_scheme:Variable]
+
+# [DEF:get_current_user:Function]
+# @PURPOSE: Dependency for retrieving the currently authenticated user from a JWT.
+# @PRE:     JWT token provided in Authorization header.
+# @POST:    Returns the User object if token is valid.
+# @THROW:   HTTPException 401 if token is invalid or user not found.
+# @PARAM:   token (str) - Extracted JWT token.
+# @PARAM:   db (Session) - Auth database session.
+# @RETURN:  User - The authenticated user.
+def get_current_user(token: str = Depends(oauth2_scheme), db = Depends(get_auth_db)):
+    with belief_scope("get_current_user"):
+        credentials_exception = HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Could not validate credentials",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+        try:
+            payload = decode_token(token)
+            username: str = payload.get("sub")
+            if username is None:
+                raise credentials_exception
+        except JWTError:
+            raise credentials_exception
+            
+        repo = AuthRepository(db)
+        user = repo.get_user_by_username(username)
+        if user is None:
+            raise credentials_exception
+        return user
+# [/DEF:get_current_user:Function]
+
+# [DEF:has_permission:Function]
+# @PURPOSE: Dependency for checking if the current user has a specific permission.
+# @PRE:     User is authenticated.
+# @POST:    Returns True if user has permission.
+# @THROW:   HTTPException 403 if permission is denied.
+# @PARAM:   resource (str) - The resource identifier.
+# @PARAM:   action (str) - The action identifier (READ, EXECUTE, WRITE).
+# @RETURN:  User - The authenticated user if permission granted.
+def has_permission(resource: str, action: str):
+    def permission_checker(current_user: User = Depends(get_current_user)):
+        with belief_scope("has_permission", f"{resource}:{action}"):
+            # Union of all permissions across all roles
+            for role in current_user.roles:
+                for perm in role.permissions:
+                    if perm.resource == resource and perm.action == action:
+                        return current_user
+            
+            # Special case for Admin role (full access)
+            if any(role.name == "Admin" for role in current_user.roles):
+                return current_user
+            
+            from .core.auth.logger import log_security_event
+            log_security_event("PERMISSION_DENIED", current_user.username, {"resource": resource, "action": action})
+                
+            raise HTTPException(
+                status_code=status.HTTP_403_FORBIDDEN,
+                detail=f"Permission denied for {resource}:{action}"
+            )
+    return permission_checker
+# [/DEF:has_permission:Function]
+
 # [/DEF:Dependencies:Module]
\ No newline at end of file
diff --git a/backend/src/models/auth.py b/backend/src/models/auth.py
new file mode 100644
index 0000000..fbbc736
--- /dev/null
+++ b/backend/src/models/auth.py
@@ -0,0 +1,104 @@
+# [DEF:backend.src.models.auth:Module]
+#
+# @SEMANTICS: auth, models, user, role, permission, sqlalchemy
+# @PURPOSE:   SQLAlchemy models for multi-user authentication and authorization.
+# @LAYER:     Domain
+# @RELATION:  INHERITS_FROM -> backend.src.models.mapping.Base
+#
+# @INVARIANT: Usernames and emails must be unique.
+
+# [SECTION: IMPORTS]
+import uuid
+from datetime import datetime
+from sqlalchemy import Column, String, Boolean, DateTime, ForeignKey, Table, Enum
+from sqlalchemy.orm import relationship
+from .mapping import Base
+# [/SECTION]
+
+# [DEF:generate_uuid:Function]
+# @PURPOSE: Generates a unique UUID string.
+# @POST:    Returns a string representation of a new UUID.
+def generate_uuid():
+    return str(uuid.uuid4())
+# [/DEF:generate_uuid:Function]
+
+# [DEF:user_roles:Table]
+# @PURPOSE: Association table for many-to-many relationship between Users and Roles.
+user_roles = Table(
+    "user_roles",
+    Base.metadata,
+    Column("user_id", String, ForeignKey("users.id"), primary_key=True),
+    Column("role_id", String, ForeignKey("roles.id"), primary_key=True),
+)
+# [/DEF:user_roles:Table]
+
+# [DEF:role_permissions:Table]
+# @PURPOSE: Association table for many-to-many relationship between Roles and Permissions.
+role_permissions = Table(
+    "role_permissions",
+    Base.metadata,
+    Column("role_id", String, ForeignKey("roles.id"), primary_key=True),
+    Column("permission_id", String, ForeignKey("permissions.id"), primary_key=True),
+)
+# [/DEF:role_permissions:Table]
+
+# [DEF:User:Class]
+# @PURPOSE: Represents an identity that can authenticate to the system.
+# @RELATION: HAS_MANY -> Role (via user_roles)
+class User(Base):
+    __tablename__ = "users"
+    
+    id = Column(String, primary_key=True, default=generate_uuid)
+    username = Column(String, unique=True, index=True, nullable=False)
+    email = Column(String, unique=True, index=True, nullable=True)
+    password_hash = Column(String, nullable=True)
+    auth_source = Column(String, default="LOCAL") # LOCAL or ADFS
+    is_active = Column(Boolean, default=True)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    last_login = Column(DateTime, nullable=True)
+    
+    roles = relationship("Role", secondary=user_roles, back_populates="users")
+# [/DEF:User:Class]
+
+# [DEF:Role:Class]
+# @PURPOSE: Represents a collection of permissions.
+# @RELATION: HAS_MANY -> User (via user_roles)
+# @RELATION: HAS_MANY -> Permission (via role_permissions)
+class Role(Base):
+    __tablename__ = "roles"
+    
+    id = Column(String, primary_key=True, default=generate_uuid)
+    name = Column(String, unique=True, index=True, nullable=False)
+    description = Column(String, nullable=True)
+    
+    users = relationship("User", secondary=user_roles, back_populates="roles")
+    permissions = relationship("Permission", secondary=role_permissions, back_populates="roles")
+# [/DEF:Role:Class]
+
+# [DEF:Permission:Class]
+# @PURPOSE: Represents a specific capability within the system.
+# @RELATION: HAS_MANY -> Role (via role_permissions)
+class Permission(Base):
+    __tablename__ = "permissions"
+    
+    id = Column(String, primary_key=True, default=generate_uuid)
+    resource = Column(String, nullable=False) # e.g. "plugin:backup"
+    action = Column(String, nullable=False)   # e.g. "READ", "EXECUTE", "WRITE"
+    
+    roles = relationship("Role", secondary=role_permissions, back_populates="permissions")
+# [/DEF:Permission:Class]
+
+# [DEF:ADGroupMapping:Class]
+# @PURPOSE: Maps an Active Directory group to a local System Role.
+# @RELATION: DEPENDS_ON -> Role
+class ADGroupMapping(Base):
+    __tablename__ = "ad_group_mappings"
+    
+    id = Column(String, primary_key=True, default=generate_uuid)
+    ad_group_name = Column(String, unique=True, index=True, nullable=False)
+    role_id = Column(String, ForeignKey("roles.id"), nullable=False)
+    
+    role = relationship("Role")
+# [/DEF:ADGroupMapping:Class]
+
+# [/DEF:backend.src.models.auth:Module]
\ No newline at end of file
diff --git a/backend/src/schemas/auth.py b/backend/src/schemas/auth.py
new file mode 100644
index 0000000..e640f6a
--- /dev/null
+++ b/backend/src/schemas/auth.py
@@ -0,0 +1,124 @@
+# [DEF:backend.src.schemas.auth:Module]
+#
+# @SEMANTICS: auth, schemas, pydantic, user, token
+# @PURPOSE:   Pydantic schemas for authentication requests and responses.
+# @LAYER:     API
+# @RELATION:  DEPENDS_ON -> pydantic
+#
+# @INVARIANT: Sensitive fields like password must not be included in response schemas.
+
+# [SECTION: IMPORTS]
+from typing import List, Optional
+from pydantic import BaseModel, EmailStr, Field
+from datetime import datetime
+# [/SECTION]
+
+# [DEF:Token:Class]
+# @PURPOSE: Represents a JWT access token response.
+class Token(BaseModel):
+    access_token: str
+    token_type: str
+# [/DEF:Token:Class]
+
+# [DEF:TokenData:Class]
+# @PURPOSE: Represents the data encoded in a JWT token.
+class TokenData(BaseModel):
+    username: Optional[str] = None
+    scopes: List[str] = []
+# [/DEF:TokenData:Class]
+
+# [DEF:PermissionSchema:Class]
+# @PURPOSE: Represents a permission in API responses.
+class PermissionSchema(BaseModel):
+    id: Optional[str] = None
+    resource: str
+    action: str
+
+    class Config:
+        from_attributes = True
+# [/DEF:PermissionSchema:Class]
+
+# [DEF:RoleSchema:Class]
+# @PURPOSE: Represents a role in API responses.
+class RoleSchema(BaseModel):
+    id: str
+    name: str
+    description: Optional[str] = None
+    permissions: List[PermissionSchema] = []
+
+    class Config:
+        from_attributes = True
+# [/DEF:RoleSchema:Class]
+
+# [DEF:RoleCreate:Class]
+# @PURPOSE: Schema for creating a new role.
+class RoleCreate(BaseModel):
+    name: str
+    description: Optional[str] = None
+    permissions: List[str] = [] # List of permission IDs or "resource:action" strings
+# [/DEF:RoleCreate:Class]
+
+# [DEF:RoleUpdate:Class]
+# @PURPOSE: Schema for updating an existing role.
+class RoleUpdate(BaseModel):
+    name: Optional[str] = None
+    description: Optional[str] = None
+    permissions: Optional[List[str]] = None
+# [/DEF:RoleUpdate:Class]
+
+# [DEF:ADGroupMappingSchema:Class]
+# @PURPOSE: Represents an AD Group to Role mapping in API responses.
+class ADGroupMappingSchema(BaseModel):
+    id: str
+    ad_group: str
+    role_id: str
+
+    class Config:
+        from_attributes = True
+# [/DEF:ADGroupMappingSchema:Class]
+
+# [DEF:ADGroupMappingCreate:Class]
+# @PURPOSE: Schema for creating an AD Group mapping.
+class ADGroupMappingCreate(BaseModel):
+    ad_group: str
+    role_id: str
+# [/DEF:ADGroupMappingCreate:Class]
+
+# [DEF:UserBase:Class]
+# @PURPOSE: Base schema for user data.
+class UserBase(BaseModel):
+    username: str
+    email: Optional[EmailStr] = None
+    is_active: bool = True
+# [/DEF:UserBase:Class]
+
+# [DEF:UserCreate:Class]
+# @PURPOSE: Schema for creating a new user.
+class UserCreate(UserBase):
+    password: str
+    roles: List[str] = []
+# [/DEF:UserCreate:Class]
+
+# [DEF:UserUpdate:Class]
+# @PURPOSE: Schema for updating an existing user.
+class UserUpdate(BaseModel):
+    email: Optional[EmailStr] = None
+    password: Optional[str] = None
+    is_active: Optional[bool] = None
+    roles: Optional[List[str]] = None
+# [/DEF:UserUpdate:Class]
+
+# [DEF:User:Class]
+# @PURPOSE: Schema for user data in API responses.
+class User(UserBase):
+    id: str
+    auth_source: str
+    created_at: datetime
+    last_login: Optional[datetime] = None
+    roles: List[RoleSchema] = []
+
+    class Config:
+        from_attributes = True
+# [/DEF:User:Class]
+
+# [/DEF:backend.src.schemas.auth:Module]
\ No newline at end of file
diff --git a/backend/src/scripts/create_admin.py b/backend/src/scripts/create_admin.py
new file mode 100644
index 0000000..52cdbce
--- /dev/null
+++ b/backend/src/scripts/create_admin.py
@@ -0,0 +1,82 @@
+# [DEF:backend.src.scripts.create_admin:Module]
+#
+# @SEMANTICS: admin, setup, user, auth, cli
+# @PURPOSE:   CLI tool for creating the initial admin user.
+# @LAYER:     Scripts
+# @RELATION:  USES -> backend.src.core.auth.security
+# @RELATION:  USES -> backend.src.core.database
+# @RELATION:  USES -> backend.src.models.auth
+#
+# @INVARIANT: Admin user must have the "Admin" role.
+
+# [SECTION: IMPORTS]
+import sys
+import argparse
+from pathlib import Path
+
+# Add src to path
+sys.path.append(str(Path(__file__).parent.parent.parent))
+
+from src.core.database import AuthSessionLocal, init_db
+from src.core.auth.security import get_password_hash
+from src.models.auth import User, Role, Permission
+from src.core.logger import logger, belief_scope
+# [/SECTION]
+
+# [DEF:create_admin:Function]
+# @PURPOSE: Creates an admin user and necessary roles/permissions.
+# @PRE:     username and password provided via CLI.
+# @POST:    Admin user exists in auth.db.
+#
+# @PARAM:   username (str) - Admin username.
+# @PARAM:   password (str) - Admin password.
+def create_admin(username, password):
+    with belief_scope("create_admin"):
+        db = AuthSessionLocal()
+        try:
+            # 1. Ensure Admin role exists
+            admin_role = db.query(Role).filter(Role.name == "Admin").first()
+            if not admin_role:
+                logger.info("Creating Admin role...")
+                admin_role = Role(name="Admin", description="System Administrator")
+                db.add(admin_role)
+                db.commit()
+                db.refresh(admin_role)
+
+            # 2. Check if user already exists
+            existing_user = db.query(User).filter(User.username == username).first()
+            if existing_user:
+                logger.warning(f"User {username} already exists.")
+                return
+
+            # 3. Create Admin user
+            logger.info(f"Creating admin user: {username}")
+            new_user = User(
+                username=username,
+                password_hash=get_password_hash(password),
+                auth_source="LOCAL",
+                is_active=True
+            )
+            new_user.roles.append(admin_role)
+            db.add(new_user)
+            db.commit()
+            logger.info(f"Admin user {username} created successfully.")
+            
+        except Exception as e:
+            logger.error(f"Failed to create admin user: {e}")
+            db.rollback()
+        finally:
+            db.close()
+# [/DEF:create_admin:Function]
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Create initial admin user")
+    parser.add_argument("--username", required=True, help="Admin username")
+    parser.add_argument("--password", required=True, help="Admin password")
+    args = parser.parse_args()
+    
+    # Ensure DB is initialized before creating admin
+    init_db()
+    create_admin(args.username, args.password)
+
+# [/DEF:backend.src.scripts.create_admin:Module]
\ No newline at end of file
diff --git a/backend/src/scripts/init_auth_db.py b/backend/src/scripts/init_auth_db.py
new file mode 100644
index 0000000..7afdf70
--- /dev/null
+++ b/backend/src/scripts/init_auth_db.py
@@ -0,0 +1,44 @@
+# [DEF:backend.src.scripts.init_auth_db:Module]
+#
+# @SEMANTICS: setup, database, auth, migration
+# @PURPOSE:   Initializes the auth database and creates the necessary tables.
+# @LAYER:     Scripts
+# @RELATION:  CALLS -> backend.src.core.database.init_db
+#
+# @INVARIANT: Safe to run multiple times (idempotent).
+
+# [SECTION: IMPORTS]
+import sys
+import os
+from pathlib import Path
+
+# Add src to path
+sys.path.append(str(Path(__file__).parent.parent.parent))
+
+from src.core.database import init_db, auth_engine
+from src.core.logger import logger, belief_scope
+from src.scripts.seed_permissions import seed_permissions
+# [/SECTION]
+
+# [DEF:run_init:Function]
+# @PURPOSE: Main entry point for the initialization script.
+# @POST:    auth.db is initialized with the correct schema and seeded permissions.
+def run_init():
+    with belief_scope("init_auth_db"):
+        logger.info("Initializing authentication database...")
+        try:
+            init_db()
+            logger.info("Authentication database initialized successfully.")
+            
+            # Seed permissions
+            seed_permissions()
+            
+        except Exception as e:
+            logger.error(f"Failed to initialize authentication database: {e}")
+            sys.exit(1)
+# [/DEF:run_init:Function]
+
+if __name__ == "__main__":
+    run_init()
+
+# [/DEF:backend.src.scripts.init_auth_db:Module]
\ No newline at end of file
diff --git a/backend/src/scripts/seed_permissions.py b/backend/src/scripts/seed_permissions.py
new file mode 100644
index 0000000..e9ece8e
--- /dev/null
+++ b/backend/src/scripts/seed_permissions.py
@@ -0,0 +1,79 @@
+# [DEF:backend.src.scripts.seed_permissions:Module]
+#
+# @SEMANTICS: setup, database, auth, permissions, seeding
+# @PURPOSE:   Populates the auth database with initial system permissions.
+# @LAYER:     Scripts
+# @RELATION:  USES -> backend.src.core.database.get_auth_db
+# @RELATION:  USES -> backend.src.models.auth.Permission
+#
+# @INVARIANT: Safe to run multiple times (idempotent).
+
+# [SECTION: IMPORTS]
+import sys
+from pathlib import Path
+
+# Add src to path
+sys.path.append(str(Path(__file__).parent.parent.parent))
+
+from src.core.database import AuthSessionLocal
+from src.models.auth import Permission
+from src.core.logger import logger, belief_scope
+# [/SECTION]
+
+# [DEF:INITIAL_PERMISSIONS:Constant]
+INITIAL_PERMISSIONS = [
+    # Admin Permissions
+    {"resource": "admin:users", "action": "READ"},
+    {"resource": "admin:users", "action": "WRITE"},
+    {"resource": "admin:roles", "action": "READ"},
+    {"resource": "admin:roles", "action": "WRITE"},
+    {"resource": "admin:settings", "action": "READ"},
+    {"resource": "admin:settings", "action": "WRITE"},
+    
+    # Plugin Permissions
+    {"resource": "plugin:backup", "action": "EXECUTE"},
+    {"resource": "plugin:migration", "action": "EXECUTE"},
+    {"resource": "plugin:mapper", "action": "EXECUTE"},
+    {"resource": "plugin:search", "action": "EXECUTE"},
+    {"resource": "plugin:git", "action": "EXECUTE"},
+    {"resource": "plugin:storage", "action": "EXECUTE"},
+    {"resource": "plugin:debug", "action": "EXECUTE"},
+]
+# [/DEF:INITIAL_PERMISSIONS:Constant]
+
+# [DEF:seed_permissions:Function]
+# @PURPOSE: Inserts missing permissions into the database.
+# @POST:    All INITIAL_PERMISSIONS exist in the DB.
+def seed_permissions():
+    with belief_scope("seed_permissions"):
+        db = AuthSessionLocal()
+        try:
+            logger.info("Seeding permissions...")
+            count = 0
+            for perm_data in INITIAL_PERMISSIONS:
+                exists = db.query(Permission).filter(
+                    Permission.resource == perm_data["resource"],
+                    Permission.action == perm_data["action"]
+                ).first()
+                
+                if not exists:
+                    new_perm = Permission(
+                        resource=perm_data["resource"],
+                        action=perm_data["action"]
+                    )
+                    db.add(new_perm)
+                    count += 1
+            
+            db.commit()
+            logger.info(f"Seeding completed. Added {count} new permissions.")
+        except Exception as e:
+            logger.error(f"Failed to seed permissions: {e}")
+            db.rollback()
+        finally:
+            db.close()
+# [/DEF:seed_permissions:Function]
+
+if __name__ == "__main__":
+    seed_permissions()
+
+# [/DEF:backend.src.scripts.seed_permissions:Module]
\ No newline at end of file
diff --git a/backend/src/services/auth_service.py b/backend/src/services/auth_service.py
new file mode 100644
index 0000000..a25e479
--- /dev/null
+++ b/backend/src/services/auth_service.py
@@ -0,0 +1,115 @@
+# [DEF:backend.src.services.auth_service:Module]
+#
+# @SEMANTICS: auth, service, business-logic, login, jwt
+# @PURPOSE:   Orchestrates authentication business logic.
+# @LAYER:     Service
+# @RELATION:  USES -> backend.src.core.auth.repository.AuthRepository
+# @RELATION:  USES -> backend.src.core.auth.security
+# @RELATION:  USES -> backend.src.core.auth.jwt
+#
+# @INVARIANT: Authentication must verify both credentials and account status.
+
+# [SECTION: IMPORTS]
+from typing import Optional, Dict, Any, List
+from sqlalchemy.orm import Session
+from ..models.auth import User, Role
+from ..core.auth.repository import AuthRepository
+from ..core.auth.security import verify_password, get_password_hash
+from ..core.auth.jwt import create_access_token
+from ..core.logger import belief_scope
+# [/SECTION]
+
+# [DEF:AuthService:Class]
+# @PURPOSE: Provides high-level authentication services.
+class AuthService:
+    # [DEF:__init__:Function]
+    # @PURPOSE: Initializes the service with a database session.
+    # @PARAM:   db (Session) - SQLAlchemy session.
+    def __init__(self, db: Session):
+        self.repo = AuthRepository(db)
+    # [/DEF:__init__:Function]
+
+    # [DEF:authenticate_user:Function]
+    # @PURPOSE: Authenticates a user with username and password.
+    # @PRE:     username and password are provided.
+    # @POST:    Returns User object if authentication succeeds, else None.
+    # @SIDE_EFFECT: Updates last_login timestamp on success.
+    # @PARAM:   username (str) - The username.
+    # @PARAM:   password (str) - The plain password.
+    # @RETURN:  Optional[User] - The authenticated user or None.
+    def authenticate_user(self, username: str, password: str):
+        with belief_scope("AuthService.authenticate_user"):
+            user = self.repo.get_user_by_username(username)
+            if not user:
+                return None
+            
+            if not user.is_active:
+                return None
+                
+            if not user.password_hash or not verify_password(password, user.password_hash):
+                return None
+            
+            self.repo.update_last_login(user)
+            return user
+    # [/DEF:authenticate_user:Function]
+
+    # [DEF:create_session:Function]
+    # @PURPOSE: Creates a JWT session for an authenticated user.
+    # @PRE:     user is a valid User object.
+    # @POST:    Returns a dictionary with access_token and token_type.
+    # @PARAM:   user (User) - The authenticated user.
+    # @RETURN:  Dict[str, str] - Session data.
+    def create_session(self, user) -> Dict[str, str]:
+        with belief_scope("AuthService.create_session"):
+            # Collect role names for scopes
+            scopes = [role.name for role in user.roles]
+            
+            token_data = {
+                "sub": user.username,
+                "scopes": scopes
+            }
+            
+            access_token = create_access_token(data=token_data)
+            return {
+                "access_token": access_token,
+                "token_type": "bearer"
+            }
+    # [/DEF:create_session:Function]
+
+    # [DEF:provision_adfs_user:Function]
+    # @PURPOSE: Just-In-Time (JIT) provisioning for ADFS users based on group mappings.
+    # @PRE:     user_info contains 'upn' (username), 'email', and 'groups'.
+    # @POST:    User is created/updated and assigned roles based on groups.
+    # @PARAM:   user_info (Dict[str, Any]) - Claims from ADFS token.
+    # @RETURN:  User - The provisioned user.
+    def provision_adfs_user(self, user_info: Dict[str, Any]) -> User:
+        with belief_scope("AuthService.provision_adfs_user"):
+            username = user_info.get("upn") or user_info.get("email")
+            email = user_info.get("email")
+            ad_groups = user_info.get("groups", [])
+            
+            user = self.repo.get_user_by_username(username)
+            if not user:
+                user = User(
+                    username=username,
+                    email=email,
+                    auth_source="ADFS",
+                    is_active=True
+                )
+                self.repo.db.add(user)
+            
+            # Update roles based on group mappings
+            from ..models.auth import ADGroupMapping
+            mapped_roles = self.repo.db.query(Role).join(ADGroupMapping).filter(
+                ADGroupMapping.ad_group_name.in_(ad_groups)
+            ).all()
+            
+            user.roles = mapped_roles
+            self.repo.db.commit()
+            self.repo.db.refresh(user)
+            return user
+    # [/DEF:provision_adfs_user:Function]
+
+# [/DEF:AuthService:Class]
+
+# [/DEF:backend.src.services.auth_service:Module]
\ No newline at end of file
diff --git a/backend/tasks.db b/backend/tasks.db
index bfa202c..4b3be6a 100644
Binary files a/backend/tasks.db and b/backend/tasks.db differ
diff --git a/frontend/src/components/Navbar.svelte b/frontend/src/components/Navbar.svelte
index d91004e..5a7c7e7 100644
--- a/frontend/src/components/Navbar.svelte
+++ b/frontend/src/components/Navbar.svelte
@@ -9,6 +9,13 @@
     import { page } from '$app/stores';
     import { t } from '$lib/i18n';
     import { LanguageSwitcher } from '$lib/ui';
+    import { auth } from '../lib/auth/store';
+    import { goto } from '$app/navigation';
+
+    function handleLogout() {
+        auth.logout();
+        goto('/login');
+    }
 </script>
 
 <header class="bg-white shadow-md p-4 flex justify-between items-center">
@@ -41,7 +48,32 @@
                 <a href="/settings/git" class="block px-4 py-2 text-sm text-gray-700 hover:bg-blue-50 hover:text-blue-600">{$t.nav.settings_git}</a>
             </div>
         </div>
+
+        {#if $auth.isAuthenticated && $auth.user?.roles?.some(r => r.name === 'Admin')}
+            <div class="relative inline-block group">
+                <button class="text-gray-600 hover:text-blue-600 font-medium pb-1 {$page.url.pathname.startsWith('/admin') ? 'text-blue-600 border-b-2 border-blue-600' : ''}">
+                    {$t.nav.admin}
+                </button>
+                <div class="absolute hidden group-hover:block bg-white shadow-lg rounded-md mt-1 py-2 w-48 z-10 border border-gray-100 before:absolute before:-top-2 before:left-0 before:right-0 before:h-2 before:content-[''] right-0">
+                    <a href="/admin/users" class="block px-4 py-2 text-sm text-gray-700 hover:bg-blue-50 hover:text-blue-600">{$t.nav.admin_users}</a>
+                    <a href="/admin/roles" class="block px-4 py-2 text-sm text-gray-700 hover:bg-blue-50 hover:text-blue-600">{$t.nav.admin_roles}</a>
+                    <a href="/admin/settings" class="block px-4 py-2 text-sm text-gray-700 hover:bg-blue-50 hover:text-blue-600">{$t.nav.admin_settings}</a>
+                </div>
+            </div>
+        {/if}
         <LanguageSwitcher />
+        
+        {#if $auth.isAuthenticated}
+            <div class="flex items-center space-x-2 border-l pl-4 ml-4">
+                <span class="text-sm text-gray-600">{$auth.user?.username}</span>
+                <button
+                    on:click={handleLogout}
+                    class="text-sm text-red-600 hover:text-red-800 font-medium"
+                >
+                    Logout
+                </button>
+            </div>
+        {/if}
     </nav>
 </header>
 <!-- [/DEF:Navbar:Component] -->
diff --git a/frontend/src/components/auth/ProtectedRoute.svelte b/frontend/src/components/auth/ProtectedRoute.svelte
new file mode 100644
index 0000000..a195689
--- /dev/null
+++ b/frontend/src/components/auth/ProtectedRoute.svelte
@@ -0,0 +1,61 @@
+<!-- [DEF:ProtectedRoute:Component] -->
+<!--
+@SEMANTICS: auth, guard, route, protection
+@PURPOSE:   Wraps content to ensure only authenticated users can access it.
+@LAYER:     Component
+@RELATION:  USES -> authStore
+@RELATION:  CALLS -> goto
+
+@INVARIANT: Redirects to /login if user is not authenticated.
+-->
+
+<script lang="ts">
+    import { onMount } from 'svelte';
+    import { auth } from '../../lib/auth/store';
+    import { goto } from '$app/navigation';
+
+    // [SECTION: TEMPLATE]
+    // Only render slot if authenticated
+    // [/SECTION: TEMPLATE]
+
+    onMount(async () => {
+        // Check if we have a token but no user profile yet
+        if ($auth.token && !$auth.user) {
+            auth.setLoading(true);
+            try {
+                const response = await fetch('/api/auth/me', {
+                    headers: {
+                        'Authorization': `Bearer ${$auth.token}`
+                    }
+                });
+                
+                if (response.ok) {
+                    const user = await response.json();
+                    auth.setUser(user);
+                } else {
+                    // Token invalid or expired
+                    auth.logout();
+                    goto('/login');
+                }
+            } catch (e) {
+                console.error('Failed to verify session:', e);
+                auth.logout();
+                goto('/login');
+            } finally {
+                auth.setLoading(false);
+            }
+        } else if (!$auth.token) {
+            goto('/login');
+        }
+    });
+</script>
+
+{#if $auth.loading}
+    <div class="flex items-center justify-center min-h-screen">
+        <div class="animate-spin rounded-full h-12 w-12 border-b-2 border-blue-600"></div>
+    </div>
+{:else if $auth.isAuthenticated}
+    <slot />
+{/if}
+
+<!-- [/DEF:ProtectedRoute:Component] -->
\ No newline at end of file
diff --git a/frontend/src/lib/api.js b/frontend/src/lib/api.js
index c950422..2b960fe 100755
--- a/frontend/src/lib/api.js
+++ b/frontend/src/lib/api.js
@@ -25,6 +25,22 @@ export const getWsUrl = (taskId) => {
 };
 // [/DEF:getWsUrl:Function]
 
+// [DEF:getAuthHeaders:Function]
+// @PURPOSE: Returns headers with Authorization if token exists.
+function getAuthHeaders() {
+    const headers = {
+        'Content-Type': 'application/json',
+    };
+    if (typeof window !== 'undefined') {
+        const token = localStorage.getItem('auth_token');
+        if (token) {
+            headers['Authorization'] = `Bearer ${token}`;
+        }
+    }
+    return headers;
+}
+// [/DEF:getAuthHeaders:Function]
+
 // [DEF:fetchApi:Function]
 // @PURPOSE: Generic GET request wrapper.
 // @PRE: endpoint string is provided.
@@ -34,7 +50,9 @@ export const getWsUrl = (taskId) => {
 async function fetchApi(endpoint) {
     try {
         console.log(`[api.fetchApi][Action] Fetching from context={{'endpoint': '${endpoint}'}}`);
-        const response = await fetch(`${API_BASE_URL}${endpoint}`);
+        const response = await fetch(`${API_BASE_URL}${endpoint}`, {
+            headers: getAuthHeaders()
+        });
         if (!response.ok) {
             throw new Error(`API request failed with status ${response.status}`);
         }
@@ -59,9 +77,7 @@ async function postApi(endpoint, body) {
         console.log(`[api.postApi][Action] Posting to context={{'endpoint': '${endpoint}'}}`);
         const response = await fetch(`${API_BASE_URL}${endpoint}`, {
             method: 'POST',
-            headers: {
-                'Content-Type': 'application/json',
-            },
+            headers: getAuthHeaders(),
             body: JSON.stringify(body),
         });
         if (!response.ok) {
@@ -85,9 +101,7 @@ async function requestApi(endpoint, method = 'GET', body = null) {
         console.log(`[api.requestApi][Action] ${method} to context={{'endpoint': '${endpoint}'}}`);
         const options = {
             method,
-            headers: {
-                'Content-Type': 'application/json',
-            },
+            headers: getAuthHeaders(),
         };
         if (body) {
             options.body = JSON.stringify(body);
@@ -112,6 +126,9 @@ async function requestApi(endpoint, method = 'GET', body = null) {
 // [DEF:api:Data]
 // @PURPOSE: API client object with specific methods.
 export const api = {
+    fetchApi,
+    postApi,
+    requestApi,
     getPlugins: () => fetchApi('/plugins'),
     getTasks: () => fetchApi('/tasks'),
     getTask: (taskId) => fetchApi(`/tasks/${taskId}`),
diff --git a/frontend/src/routes/+layout.svelte b/frontend/src/routes/+layout.svelte
index 4fd5373..e41db53 100644
--- a/frontend/src/routes/+layout.svelte
+++ b/frontend/src/routes/+layout.svelte
@@ -3,16 +3,28 @@
     import Navbar from '../components/Navbar.svelte';
     import Footer from '../components/Footer.svelte';
     import Toast from '../components/Toast.svelte';
+    import ProtectedRoute from '../components/auth/ProtectedRoute.svelte';
+    import { page } from '$app/stores';
+
+    $: isLoginPage = $page.url.pathname === '/login';
 </script>
 
 <Toast />
 
 <main class="bg-gray-50 min-h-screen flex flex-col">
-    <Navbar />
+    {#if isLoginPage}
+        <div class="p-4 flex-grow">
+            <slot />
+        </div>
+    {:else}
+        <ProtectedRoute>
+            <Navbar />
 
-    <div class="p-4 flex-grow">
-        <slot />
-    </div>
+            <div class="p-4 flex-grow">
+                <slot />
+            </div>
 
-    <Footer />
+            <Footer />
+        </ProtectedRoute>
+    {/if}
 </main>
diff --git a/frontend/src/routes/admin/roles/+page.svelte b/frontend/src/routes/admin/roles/+page.svelte
new file mode 100644
index 0000000..1924e66
--- /dev/null
+++ b/frontend/src/routes/admin/roles/+page.svelte
@@ -0,0 +1,216 @@
+<!-- [DEF:AdminRolesPage:Component] -->
+<!--
+@SEMANTICS: admin, role-management, rbac
+@PURPOSE:   UI for managing system roles and their permissions.
+@LAYER:     Feature
+@RELATION:  DEPENDS_ON -> frontend.src.services.adminService
+@RELATION:  DEPENDS_ON -> frontend.src.components.auth.ProtectedRoute
+
+@INVARIANT: Only accessible by users with Admin role.
+-->
+
+<script lang="ts">
+  // [SECTION: IMPORTS]
+  import { onMount } from 'svelte';
+  import { t } from '$lib/i18n';
+  import ProtectedRoute from '../../../components/auth/ProtectedRoute.svelte';
+  import { adminService } from '../../../services/adminService';
+  // [/SECTION: IMPORTS]
+
+  let roles = [];
+  let permissions = [];
+  let loading = true;
+  let error = null;
+
+  let showModal = false;
+  let isEditing = false;
+  let currentRoleId = null;
+  let roleForm = {
+    name: '',
+    description: '',
+    permissions: []
+  };
+
+  // [DEF:loadData:Function]
+  /**
+   * @purpose Fetches roles and available permissions.
+   * @pre     Component mounted.
+   * @post    roles and permissions arrays populated.
+   */
+  async function loadData() {
+    console.log('[AdminRolesPage][loadData][Entry]');
+    loading = true;
+    try {
+      [roles, permissions] = await Promise.all([
+        adminService.getRoles(),
+        adminService.getPermissions()
+      ]);
+      console.log('[AdminRolesPage][loadData][Coherence:OK]');
+    } catch (e) {
+      error = "Failed to load roles data.";
+      console.error('[AdminRolesPage][loadData][Coherence:Failed]', e);
+    } finally {
+      loading = false;
+    }
+  }
+  // [/DEF:loadData:Function]
+
+  // [DEF:openCreateModal:Function]
+  function openCreateModal() {
+    isEditing = false;
+    currentRoleId = null;
+    roleForm = { name: '', description: '', permissions: [] };
+    showModal = true;
+  }
+  // [/DEF:openCreateModal:Function]
+
+  // [DEF:openEditModal:Function]
+  function openEditModal(role) {
+    isEditing = true;
+    currentRoleId = role.id;
+    roleForm = {
+      name: role.name,
+      description: role.description || '',
+      permissions: role.permissions.map(p => p.id)
+    };
+    showModal = true;
+  }
+  // [/DEF:openEditModal:Function]
+
+  // [DEF:handleSaveRole:Function]
+  /**
+   * @purpose Submits role data (create or update).
+   */
+  async function handleSaveRole() {
+    console.log('[AdminRolesPage][handleSaveRole][Entry]');
+    try {
+      if (isEditing) {
+        await adminService.updateRole(currentRoleId, roleForm);
+      } else {
+        await adminService.createRole(roleForm);
+      }
+      showModal = false;
+      await loadData();
+      console.log('[AdminRolesPage][handleSaveRole][Coherence:OK]');
+    } catch (e) {
+      alert("Failed to save role: " + e.message);
+      console.error('[AdminRolesPage][handleSaveRole][Coherence:Failed]', e);
+    }
+  }
+  // [/DEF:handleSaveRole:Function]
+
+  // [DEF:handleDeleteRole:Function]
+  async function handleDeleteRole(role) {
+    if (!confirm($t.admin.roles.confirm_delete.replace('{name}', role.name))) return;
+    
+    console.log('[AdminRolesPage][handleDeleteRole][Entry]');
+    try {
+      await adminService.deleteRole(role.id);
+      await loadData();
+      console.log('[AdminRolesPage][handleDeleteRole][Coherence:OK]');
+    } catch (e) {
+      alert("Failed to delete role: " + e.message);
+      console.error('[AdminRolesPage][handleDeleteRole][Coherence:Failed]', e);
+    }
+  }
+  // [/DEF:handleDeleteRole:Function]
+
+  onMount(loadData);
+</script>
+
+<ProtectedRoute requiredPermission="admin:roles">
+  <!-- [SECTION: TEMPLATE] -->
+  <div class="container mx-auto p-4">
+    <div class="flex justify-between items-center mb-6">
+      <h1 class="text-2xl font-bold">{$t.admin.roles.title}</h1>
+      <button
+        class="bg-blue-600 text-white px-4 py-2 rounded hover:bg-blue-700"
+        on:click={openCreateModal}
+      >
+        {$t.admin.roles.create}
+      </button>
+    </div>
+
+    {#if loading}
+      <p>{$t.admin.roles.loading}</p>
+    {:else if error}
+      <div class="bg-red-100 text-red-700 p-4 rounded">{error}</div>
+    {:else}
+      <div class="bg-white shadow rounded-lg overflow-hidden">
+        <table class="min-w-full divide-y divide-gray-200">
+          <thead class="bg-gray-50">
+            <tr>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.roles.name}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.roles.description}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.roles.permissions}</th>
+              <th class="px-6 py-3 text-right text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.common.actions}</th>
+            </tr>
+          </thead>
+          <tbody class="bg-white divide-y divide-gray-200">
+            {#each roles as role}
+              <tr>
+                <td class="px-6 py-4 whitespace-nowrap font-medium">{role.name}</td>
+                <td class="px-6 py-4 whitespace-nowrap text-sm text-gray-500">{role.description || '-'}</td>
+                <td class="px-6 py-4">
+                  <div class="flex flex-wrap gap-1">
+                    {#each role.permissions as perm}
+                      <span class="px-2 py-0.5 bg-blue-50 text-blue-700 text-xs rounded border border-blue-100">
+                        {perm.resource}:{perm.action}
+                      </span>
+                    {/each}
+                  </div>
+                </td>
+                <td class="px-6 py-4 whitespace-nowrap text-right text-sm font-medium">
+                  <button on:click={() => openEditModal(role)} class="text-blue-600 hover:text-blue-900 mr-3">{$t.common.edit}</button>
+                  <button on:click={() => handleDeleteRole(role)} class="text-red-600 hover:text-red-900">{$t.common.delete}</button>
+                </td>
+              </tr>
+            {/each}
+          </tbody>
+        </table>
+      </div>
+    {/if}
+
+    {#if showModal}
+      <div class="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center p-4 z-50">
+        <div class="bg-white rounded-lg p-6 max-w-2xl w-full max-h-[90vh] overflow-y-auto">
+          <h2 class="text-xl font-bold mb-4">
+            {isEditing ? $t.admin.roles.modal_edit_title : $t.admin.roles.modal_create_title}
+          </h2>
+          <form on:submit|preventDefault={handleSaveRole}>
+            <div class="mb-4">
+              <label class="block text-sm font-medium mb-1">{$t.admin.roles.name}</label>
+              <input type="text" bind:value={roleForm.name} class="w-full border p-2 rounded" required readonly={isEditing} />
+            </div>
+            <div class="mb-4">
+              <label class="block text-sm font-medium mb-1">{$t.admin.roles.description}</label>
+              <textarea bind:value={roleForm.description} class="w-full border p-2 rounded h-20"></textarea>
+            </div>
+            <div class="mb-6">
+              <label class="block text-sm font-medium mb-2">{$t.admin.roles.permissions}</label>
+              <div class="grid grid-cols-2 md:grid-cols-3 gap-2 border p-3 rounded bg-gray-50">
+                {#each permissions as perm}
+                  <label class="flex items-center space-x-2 p-1 hover:bg-white rounded cursor-pointer">
+                    <input type="checkbox" value={perm.id} bind:group={roleForm.permissions} class="rounded text-blue-600" />
+                    <span class="text-xs">{perm.resource}:{perm.action}</span>
+                  </label>
+                {/each}
+              </div>
+              <p class="text-xs text-gray-500 mt-2">{$t.admin.roles.permissions_hint}</p>
+            </div>
+            <div class="flex justify-end gap-2 pt-4 border-t">
+              <button type="button" class="px-4 py-2 text-gray-600" on:click={() => showModal = false}>{$t.common.cancel}</button>
+              <button type="submit" class="px-4 py-2 bg-blue-600 text-white rounded hover:bg-blue-700">{$t.common.save}</button>
+            </div>
+          </form>
+        </div>
+      </div>
+    {/if}
+  </div>
+  <!-- [/SECTION: TEMPLATE] -->
+</ProtectedRoute>
+
+<style>
+</style>
+
+<!-- [/DEF:AdminRolesPage:Component] -->
\ No newline at end of file
diff --git a/frontend/src/routes/admin/settings/+page.svelte b/frontend/src/routes/admin/settings/+page.svelte
new file mode 100644
index 0000000..82f2c55
--- /dev/null
+++ b/frontend/src/routes/admin/settings/+page.svelte
@@ -0,0 +1,213 @@
+<!-- [DEF:AdminSettingsPage:Component] -->
+<!--
+@SEMANTICS: admin, adfs, mappings, configuration
+@PURPOSE:   UI for configuring Active Directory Group to local Role mappings for ADFS SSO.
+@LAYER:     Feature
+@RELATION:  DEPENDS_ON -> frontend.src.services.adminService
+@RELATION:  DEPENDS_ON -> frontend.src.components.auth.ProtectedRoute
+
+@INVARIANT: Only accessible by users with "admin:settings" permission.
+-->
+
+<script lang="ts">
+  // [SECTION: IMPORTS]
+  import { onMount } from 'svelte';
+  import { t } from '$lib/i18n';
+  import ProtectedRoute from '../../../components/auth/ProtectedRoute.svelte';
+  import { adminService } from '../../../services/adminService';
+  // [/SECTION: IMPORTS]
+
+  let mappings = [];
+  let roles = [];
+  let loading = true;
+  let error = null;
+
+  let showCreateModal = false;
+  let newMapping = {
+    ad_group: '',
+    role_id: ''
+  };
+
+  // [DEF:loadData:Function]
+  /**
+   * @purpose Fetches AD mappings and roles from the backend to populate the UI.
+   * @pre     Component is mounted and user has active session.
+   * @post    mappings and roles variables are updated with backend data.
+   * @returns {Promise<void>}
+   * @side_effect Updates local 'mappings', 'roles', 'loading', and 'error' states.
+   * @relation CALLS -> adminService.getRoles
+   * @relation CALLS -> adminService.getADGroupMappings
+   */
+  async function loadData() {
+    console.log('[AdminSettingsPage][loadData][Entry]');
+    loading = true;
+    try {
+      // Fetch roles first as they are required for displaying mapping labels
+      roles = await adminService.getRoles();
+      
+      try {
+        mappings = await adminService.getADGroupMappings();
+      } catch (e) {
+        console.warn("[AdminSettingsPage][loadData] AD Mappings endpoint potentially unavailable.");
+      }
+      
+      console.log('[AdminSettingsPage][loadData][Coherence:OK]');
+    } catch (e) {
+      error = "Failed to load roles or configuration.";
+      console.error('[AdminSettingsPage][loadData][Coherence:Failed]', e);
+    } finally {
+      loading = false;
+    }
+  }
+  // [/DEF:loadData:Function]
+
+  // [DEF:handleCreateMapping:Function]
+  /**
+   * @purpose Submits a new AD Group to Role mapping to the backend.
+   * @pre     'newMapping' object contains valid 'ad_group' and 'role_id'.
+   * @post    A new mapping is created in the database and the table is refreshed.
+   * @returns {Promise<void>}
+   * @side_effect Closes the modal on success, shows alert on failure.
+   * @relation CALLS -> adminService.createADGroupMapping
+   */
+  async function handleCreateMapping() {
+    console.log('[AdminSettingsPage][handleCreateMapping][Entry]');
+    
+    // Guard Clause (@PRE)
+    if (!newMapping.ad_group || !newMapping.role_id) {
+        alert("Please fill in all fields.");
+        return;
+    }
+
+    try {
+      await adminService.createADGroupMapping(newMapping);
+      showCreateModal = false;
+      // Reset form
+      newMapping = { ad_group: '', role_id: '' };
+      await loadData();
+      console.log('[AdminSettingsPage][handleCreateMapping][Coherence:OK]');
+    } catch (e) {
+      alert("Failed to create mapping: " + (e.message || "Unknown error"));
+      console.error('[AdminSettingsPage][handleCreateMapping][Coherence:Failed]', e);
+    }
+  }
+  // [/DEF:handleCreateMapping:Function]
+
+  onMount(loadData);
+</script>
+
+<ProtectedRoute requiredPermission="admin:settings">
+  <!-- [SECTION: TEMPLATE] -->
+  <div class="container mx-auto p-4">
+    <div class="flex justify-between items-center mb-6">
+      <h1 class="text-2xl font-bold">{$t.admin.settings.title}</h1>
+      <button
+        class="bg-blue-600 text-white px-4 py-2 rounded hover:bg-blue-700 transition-colors"
+        on:click={() => showCreateModal = true}
+      >
+        {$t.admin.settings.add_mapping}
+      </button>
+    </div>
+
+    {#if loading}
+      <div class="flex justify-center py-8">
+        <p class="text-gray-500 animate-pulse">{$t.common.loading}</p>
+      </div>
+    {:else if error}
+      <div class="bg-red-100 border-l-4 border-red-500 text-red-700 p-4 rounded mb-4" role="alert">
+        <p class="font-bold">{$t.common.error}</p>
+        <p>{error}</p>
+      </div>
+    {:else}
+      <div class="bg-white shadow rounded-lg overflow-hidden border border-gray-200">
+        <table class="min-w-full divide-y divide-gray-200">
+          <thead class="bg-gray-50">
+            <tr>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.settings.ad_group}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.settings.local_role}</th>
+            </tr>
+          </thead>
+          <tbody class="bg-white divide-y divide-gray-200">
+            {#each mappings as mapping}
+              <tr class="hover:bg-gray-50 transition-colors">
+                <td class="px-6 py-4 whitespace-nowrap font-mono text-sm text-gray-600">{mapping.ad_group}</td>
+                <td class="px-6 py-4 whitespace-nowrap">
+                  <span class="px-2 py-1 bg-blue-100 text-blue-800 text-xs font-semibold rounded-full">
+                    {roles.find(r => r.id === mapping.role_id)?.name || mapping.role_id}
+                  </span>
+                </td>
+              </tr>
+            {/each}
+            {#if mappings.length === 0}
+              <tr>
+                <td colspan="2" class="px-6 py-12 text-center text-gray-500">
+                  <div class="flex flex-col items-center">
+                    <svg class="w-12 h-12 text-gray-300 mb-2" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+                      <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M9 12h6m-6 4h6m2 5H7a2 2 0 01-2-2V5a2 2 0 012-2h5.586a1 1 0 01.707.293l5.414 5.414a1 1 0 01.293.707V19a2 2 0 01-2 2z"></path>
+                    </svg>
+                    <p>{$t.admin.settings.no_mappings}</p>
+                  </div>
+                </td>
+              </tr>
+            {/if}
+          </tbody>
+        </table>
+      </div>
+    {/if}
+
+    {#if showCreateModal}
+      <div class="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center p-4 z-50">
+        <div class="bg-white rounded-lg shadow-xl p-6 max-w-md w-full">
+          <h2 class="text-xl font-bold mb-4 border-b pb-2">{$t.admin.settings.modal_title}</h2>
+          <form on:submit|preventDefault={handleCreateMapping}>
+            <div class="mb-4">
+              <label class="block text-sm font-medium text-gray-700 mb-1">{$t.admin.settings.ad_group_dn}</label>
+              <input
+                type="text"
+                bind:value={newMapping.ad_group}
+                class="w-full border border-gray-300 p-2 rounded focus:ring-2 focus:ring-blue-500 focus:border-blue-500"
+                placeholder="e.g. CN=SS_ADMINS,OU=Groups,DC=org"
+                required
+              />
+              <p class="text-xs text-gray-500 mt-1">{$t.admin.settings.ad_group_hint}</p>
+            </div>
+            <div class="mb-6">
+              <label class="block text-sm font-medium text-gray-700 mb-1">{$t.admin.settings.local_role_select}</label>
+              <select
+                bind:value={newMapping.role_id}
+                class="w-full border border-gray-300 p-2 rounded focus:ring-2 focus:ring-blue-500 focus:border-blue-500"
+                required
+              >
+                <option value="" disabled>{$t.admin.settings.select_role}</option>
+                {#each roles as role}
+                  <option value={role.id}>{role.name}</option>
+                {/each}
+              </select>
+            </div>
+            <div class="flex justify-end gap-3">
+              <button
+                type="button"
+                class="px-4 py-2 text-gray-600 hover:text-gray-800 font-medium"
+                on:click={() => showCreateModal = false}
+              >
+                {$t.common.cancel}
+              </button>
+              <button
+                type="submit"
+                class="px-6 py-2 bg-blue-600 text-white rounded font-bold hover:bg-blue-700 shadow-md"
+              >
+                {$t.common.save}
+              </button>
+            </div>
+          </form>
+        </div>
+      </div>
+    {/if}
+  </div>
+  <!-- [/SECTION: TEMPLATE] -->
+</ProtectedRoute>
+
+<style>
+</style>
+
+<!-- [/DEF:AdminSettingsPage:Component] -->
\ No newline at end of file
diff --git a/frontend/src/routes/admin/users/+page.svelte b/frontend/src/routes/admin/users/+page.svelte
new file mode 100644
index 0000000..878cf33
--- /dev/null
+++ b/frontend/src/routes/admin/users/+page.svelte
@@ -0,0 +1,273 @@
+<!-- [DEF:AdminUsersPage:Component] -->
+<!--
+@SEMANTICS: admin, user-management, rbac
+@PURPOSE:   UI for managing system users and their roles.
+@LAYER:     Feature
+@RELATION:  DEPENDS_ON -> frontend.src.services.adminService
+@RELATION:  DEPENDS_ON -> frontend.src.components.auth.ProtectedRoute
+
+@INVARIANT: Only accessible by users with "admin:users" permission.
+-->
+
+<script lang="ts">
+  // [SECTION: IMPORTS]
+  import { onMount } from 'svelte';
+  import { t } from '$lib/i18n';
+  import ProtectedRoute from '../../../components/auth/ProtectedRoute.svelte';
+  import { adminService } from '../../../services/adminService';
+  // [/SECTION: IMPORTS]
+
+  let users = [];
+  let roles = [];
+  let loading = true;
+  let error = null;
+
+  let showModal = false;
+  let isEditing = false;
+  let currentUserId = null;
+  let userForm = {
+    username: '',
+    email: '',
+    password: '',
+    roles: [],
+    is_active: true
+  };
+
+  // [DEF:loadData:Function]
+  /**
+   * @purpose Fetches users and roles from the backend.
+   * @pre     Component mounted.
+   * @post    users and roles arrays populated.
+   */
+  async function loadData() {
+    console.log('[AdminUsersPage][loadData][Entry]');
+    loading = true;
+    try {
+      [users, roles] = await Promise.all([
+        adminService.getUsers(),
+        adminService.getRoles()
+      ]);
+      console.log('[AdminUsersPage][loadData][Coherence:OK]');
+    } catch (e) {
+      error = "Failed to load admin data.";
+      console.error('[AdminUsersPage][loadData][Coherence:Failed]', e);
+    } finally {
+      loading = false;
+    }
+  }
+  // [/DEF:loadData:Function]
+
+  // [DEF:openCreateModal:Function]
+  /**
+   * @purpose Prepares the form for creating a new user.
+   * @post    showModal is true, isEditing is false, userForm is reset.
+   */
+  function openCreateModal() {
+    isEditing = false;
+    currentUserId = null;
+    userForm = { username: '', email: '', password: '', roles: [], is_active: true };
+    showModal = true;
+  }
+  // [/DEF:openCreateModal:Function]
+
+  // [DEF:openEditModal:Function]
+  /**
+   * @purpose Prepares the form for editing an existing user.
+   * @pre     user object must be valid.
+   * @post    showModal is true, isEditing is true, userForm populated with user data.
+   * @param   {Object} user - The user object to edit.
+   */
+  function openEditModal(user) {
+    isEditing = true;
+    currentUserId = user.id;
+    userForm = {
+      username: user.username,
+      email: user.email,
+      password: '',
+      roles: user.roles.map(r => r.name),
+      is_active: user.is_active
+    };
+    showModal = true;
+  }
+  // [/DEF:openEditModal:Function]
+
+  // [DEF:handleSaveUser:Function]
+  /**
+   * @purpose Submits user data to the backend (create or update).
+   * @pre     userForm must be valid.
+   * @post    User created or updated, modal closed, data reloaded.
+   * @side_effect Triggers API call to adminService.
+   * @relation CALLS -> adminService.createUser
+   * @relation CALLS -> adminService.updateUser
+   */
+  async function handleSaveUser() {
+    console.log('[AdminUsersPage][handleSaveUser][Entry]');
+    try {
+      if (isEditing) {
+        const updateData = { ...userForm };
+        if (!updateData.password) delete updateData.password;
+        await adminService.updateUser(currentUserId, updateData);
+      } else {
+        await adminService.createUser(userForm);
+      }
+      showModal = false;
+      await loadData();
+      console.log('[AdminUsersPage][handleSaveUser][Coherence:OK]');
+    } catch (e) {
+      alert("Failed to save user: " + e.message);
+      console.error('[AdminUsersPage][handleSaveUser][Coherence:Failed]', e);
+    }
+  }
+  // [/DEF:handleSaveUser:Function]
+
+  // [DEF:handleDeleteUser:Function]
+  /**
+   * @purpose Deletes a user after confirmation.
+   * @pre     user object must be valid.
+   * @post    User deleted if confirmed, data reloaded.
+   * @side_effect Triggers API call to adminService.
+   * @relation CALLS -> adminService.deleteUser
+   * @param   {Object} user - The user to delete.
+   */
+  async function handleDeleteUser(user) {
+    if (!confirm($t.admin.users.confirm_delete.replace('{username}', user.username))) return;
+    
+    console.log('[AdminUsersPage][handleDeleteUser][Entry]');
+    try {
+      await adminService.deleteUser(user.id);
+      await loadData();
+      console.log('[AdminUsersPage][handleDeleteUser][Coherence:OK]');
+    } catch (e) {
+      alert("Failed to delete user: " + e.message);
+      console.error('[AdminUsersPage][handleDeleteUser][Coherence:Failed]', e);
+    }
+  }
+  // [/DEF:handleDeleteUser:Function]
+
+  onMount(loadData);
+</script>
+
+<ProtectedRoute requiredPermission="admin:users">
+  <!-- [SECTION: TEMPLATE] -->
+  <div class="container mx-auto p-4">
+    <div class="flex justify-between items-center mb-6">
+      <h1 class="text-2xl font-bold">{$t.admin.users.title}</h1>
+      <button
+        class="bg-blue-600 text-white px-4 py-2 rounded hover:bg-blue-700 transition-colors"
+        on:click={openCreateModal}
+      >
+        {$t.admin.users.create}
+      </button>
+    </div>
+
+    {#if loading}
+      <div class="flex justify-center py-8">
+        <p class="text-gray-500 animate-pulse">{$t.common.loading}</p>
+      </div>
+    {:else if error}
+      <div class="bg-red-100 border-l-4 border-red-500 text-red-700 p-4 rounded mb-4">
+        <p class="font-bold">{$t.common.error}</p>
+        <p>{error}</p>
+      </div>
+    {:else}
+      <div class="bg-white shadow rounded-lg overflow-hidden border border-gray-200">
+        <table class="min-w-full divide-y divide-gray-200">
+          <thead class="bg-gray-50">
+            <tr>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.users.username}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.users.email}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.users.source}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.users.roles}</th>
+              <th class="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.admin.users.status}</th>
+              <th class="px-6 py-3 text-right text-xs font-medium text-gray-500 uppercase tracking-wider">{$t.common.actions}</th>
+            </tr>
+          </thead>
+          <tbody class="bg-white divide-y divide-gray-200">
+            {#each users as user}
+              <tr class="hover:bg-gray-50 transition-colors">
+                <td class="px-6 py-4 whitespace-nowrap font-medium">{user.username}</td>
+                <td class="px-6 py-4 whitespace-nowrap text-sm text-gray-500">{user.email || '-'}</td>
+                <td class="px-6 py-4 whitespace-nowrap">
+                  <span class="px-2 py-1 text-xs font-semibold rounded-full {user.auth_source === 'LOCAL' ? 'bg-blue-100 text-blue-800' : 'bg-green-100 text-green-800'}">
+                    {user.auth_source}
+                  </span>
+                </td>
+                <td class="px-6 py-4 whitespace-nowrap">
+                  <div class="flex flex-wrap gap-1">
+                    {#each user.roles as role}
+                      <span class="px-2 py-0.5 bg-gray-100 text-gray-700 text-xs rounded border border-gray-200">{role.name}</span>
+                    {/each}
+                  </div>
+                </td>
+                <td class="px-6 py-4 whitespace-nowrap">
+                  <span class="flex items-center">
+                    <span class="h-2 w-2 rounded-full mr-2 {user.is_active ? 'bg-green-500' : 'bg-red-500'}"></span>
+                    <span class="text-sm {user.is_active ? 'text-green-700' : 'text-red-700'}">
+                      {user.is_active ? $t.admin.users.active : $t.admin.users.inactive}
+                    </span>
+                  </span>
+                </td>
+                <td class="px-6 py-4 whitespace-nowrap text-right text-sm font-medium">
+                  <button on:click={() => openEditModal(user)} class="text-blue-600 hover:text-blue-900 mr-3">{$t.common.edit}</button>
+                  <button on:click={() => handleDeleteUser(user)} class="text-red-600 hover:text-red-900">{$t.common.delete}</button>
+                </td>
+              </tr>
+            {/each}
+          </tbody>
+        </table>
+      </div>
+    {/if}
+
+    {#if showModal}
+      <div class="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center p-4 z-50">
+        <div class="bg-white rounded-lg shadow-xl p-6 max-w-md w-full">
+          <h2 class="text-xl font-bold mb-4 border-b pb-2">
+            {isEditing ? $t.admin.users.modal_edit_title : $t.admin.users.modal_title}
+          </h2>
+          <form on:submit|preventDefault={handleSaveUser}>
+            <div class="mb-4">
+              <label class="block text-sm font-medium text-gray-700 mb-1">{$t.admin.users.username}</label>
+              <input type="text" bind:value={userForm.username} class="w-full border border-gray-300 p-2 rounded focus:ring-2 focus:ring-blue-500 focus:border-blue-500 bg-gray-50" required readonly={isEditing} />
+            </div>
+            <div class="mb-4">
+              <label class="block text-sm font-medium text-gray-700 mb-1">{$t.admin.users.email}</label>
+              <input type="email" bind:value={userForm.email} class="w-full border border-gray-300 p-2 rounded focus:ring-2 focus:ring-blue-500 focus:border-blue-500" required />
+            </div>
+            <div class="mb-4">
+              <label class="block text-sm font-medium text-gray-700 mb-1">{$t.admin.users.password}</label>
+              <input type="password" bind:value={userForm.password} class="w-full border border-gray-300 p-2 rounded focus:ring-2 focus:ring-blue-500 focus:border-blue-500" required={!isEditing} />
+              {#if isEditing}
+                <p class="text-xs text-gray-500 mt-1">{$t.admin.users.password_hint}</p>
+              {/if}
+            </div>
+            <div class="mb-4">
+              <label class="flex items-center space-x-2 cursor-pointer">
+                <input type="checkbox" bind:checked={userForm.is_active} class="rounded text-blue-600 focus:ring-blue-500" />
+                <span class="text-sm font-medium text-gray-700">{$t.admin.users.active}</span>
+              </label>
+            </div>
+            <div class="mb-6">
+              <label class="block text-sm font-medium text-gray-700 mb-1">{$t.admin.users.roles}</label>
+              <select multiple bind:value={userForm.roles} class="w-full border border-gray-300 p-2 rounded focus:ring-2 focus:ring-blue-500 focus:border-blue-500 h-32">
+                {#each roles as role}
+                  <option value={role.name}>{role.name}</option>
+                {/each}
+              </select>
+              <p class="text-xs text-gray-500 mt-1">{$t.admin.users.roles_hint}</p>
+            </div>
+            <div class="flex justify-end gap-3 pt-4 border-t">
+              <button type="button" class="px-4 py-2 text-gray-600 hover:text-gray-800 font-medium" on:click={() => showModal = false}>{$t.common.cancel}</button>
+              <button type="submit" class="px-6 py-2 bg-blue-600 text-white rounded font-bold hover:bg-blue-700 shadow-md transition-colors">{$t.common.save}</button>
+            </div>
+          </form>
+        </div>
+      </div>
+    {/if}
+  </div>
+  <!-- [/SECTION: TEMPLATE] -->
+</ProtectedRoute>
+
+<style>
+</style>
+
+<!-- [/DEF:AdminUsersPage:Component] -->
diff --git a/frontend/src/routes/login/+page.svelte b/frontend/src/routes/login/+page.svelte
new file mode 100644
index 0000000..7c7dd97
--- /dev/null
+++ b/frontend/src/routes/login/+page.svelte
@@ -0,0 +1,165 @@
+<!-- [DEF:LoginPage:Component] -->
+<!--
+@SEMANTICS: login, auth, ui, form
+@PURPOSE:   Provides the user interface for local and ADFS authentication.
+@LAYER:     Feature
+@RELATION:  USES -> authStore
+@RELATION:  CALLS -> api.auth.login
+
+@INVARIANT: Shows both local login form and ADFS SSO button.
+-->
+
+<script lang="ts">
+    import { onMount } from 'svelte';
+    import { auth } from '../../lib/auth/store';
+    import { goto } from '$app/navigation';
+
+    let username = '';
+    let password = '';
+    let error = '';
+    let loading = false;
+
+    // [DEF:handleLogin:Function]
+    /**
+     * @purpose Submits the local login form to the backend.
+     * @pre     Username and password are not empty.
+     * @post    User is authenticated and redirected on success.
+     */
+    async function handleLogin() {
+        if (!username || !password) {
+            error = 'Please enter both username and password';
+            return;
+        }
+
+        loading = true;
+        error = '';
+
+        try {
+            const formData = new URLSearchParams();
+            formData.append('username', username);
+            formData.append('password', password);
+
+            const response = await fetch('/api/auth/login', {
+                method: 'POST',
+                headers: {
+                    'Content-Type': 'application/x-www-form-urlencoded',
+                },
+                body: formData
+            });
+
+            if (response.ok) {
+                const data = await response.json();
+                auth.setToken(data.access_token);
+                
+                // Fetch user profile
+                const profileRes = await fetch('/api/auth/me', {
+                    headers: {
+                        'Authorization': `Bearer ${data.access_token}`
+                    }
+                });
+                
+                if (profileRes.ok) {
+                    const user = await profileRes.json();
+                    auth.setUser(user);
+                    goto('/');
+                } else {
+                    error = 'Failed to fetch user profile';
+                }
+            } else {
+                const errData = await response.json();
+                error = errData.detail || 'Invalid username or password';
+            }
+        } catch (e) {
+            error = 'An error occurred during login';
+            console.error(e);
+        } finally {
+            loading = false;
+        }
+    }
+    // [/DEF:handleLogin:Function]
+
+    // [DEF:handleADFSLogin:Function]
+    /**
+     * @purpose Redirects the user to the ADFS login endpoint.
+     */
+    function handleADFSLogin() {
+        window.location.href = '/api/auth/login/adfs';
+    }
+    // [/DEF:handleADFSLogin:Function]
+
+    onMount(() => {
+        if ($auth.isAuthenticated) {
+            goto('/');
+        }
+    });
+</script>
+
+<!-- [SECTION: TEMPLATE] -->
+<div class="max-w-md mx-auto mt-10 p-6 bg-white rounded-lg shadow-md">
+    <h2 class="text-2xl font-bold mb-6 text-center">Login</h2>
+
+    {#if error}
+        <div class="mb-4 p-3 bg-red-100 text-red-700 rounded border border-red-200">
+            {error}
+        </div>
+    {/if}
+
+    <form on:submit|preventDefault={handleLogin} class="space-y-4">
+        <div>
+            <label for="username" class="block text-sm font-medium text-gray-700">Username</label>
+            <input
+                type="text"
+                id="username"
+                bind:value={username}
+                class="mt-1 block w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500"
+                required
+            />
+        </div>
+
+        <div>
+            <label for="password" class="block text-sm font-medium text-gray-700">Password</label>
+            <input
+                type="password"
+                id="password"
+                bind:value={password}
+                class="mt-1 block w-full px-3 py-2 border border-gray-300 rounded-md shadow-sm focus:outline-none focus:ring-blue-500 focus:border-blue-500"
+                required
+            />
+        </div>
+
+        <button
+            type="submit"
+            disabled={loading}
+            class="w-full py-2 px-4 border border-transparent rounded-md shadow-sm text-sm font-medium text-white bg-blue-600 hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500 disabled:opacity-50"
+        >
+            {loading ? 'Logging in...' : 'Login'}
+        </button>
+    </form>
+
+    <div class="mt-6">
+        <div class="relative">
+            <div class="absolute inset-0 flex items-center">
+                <div class="w-full border-t border-gray-300"></div>
+            </div>
+            <div class="relative flex justify-center text-sm">
+                <span class="px-2 bg-white text-gray-500">Or continue with</span>
+            </div>
+        </div>
+
+        <div class="mt-6">
+            <button
+                on:click={handleADFSLogin}
+                class="w-full flex justify-center py-2 px-4 border border-gray-300 rounded-md shadow-sm text-sm font-medium text-gray-700 bg-white hover:bg-gray-50 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500"
+            >
+                Corporate SSO (ADFS)
+            </button>
+        </div>
+    </div>
+</div>
+<!-- [/SECTION: TEMPLATE] -->
+
+<style>
+    /* No additional styles needed, using Tailwind */
+</style>
+
+<!-- [/DEF:LoginPage:Component] -->
\ No newline at end of file
diff --git a/frontend/src/routes/settings/+page.svelte b/frontend/src/routes/settings/+page.svelte
index bbc7031..6062cb1 100644
--- a/frontend/src/routes/settings/+page.svelte
+++ b/frontend/src/routes/settings/+page.svelte
@@ -8,9 +8,29 @@
     /** @type {import('./$types').PageData} */
     export let data;
 
-    let settings = data.settings;
+    let settings = data.settings || {
+        environments: [],
+        settings: {
+            storage: {
+                root_path: '',
+                backup_structure_pattern: '',
+                repo_structure_pattern: '',
+                filename_pattern: ''
+            }
+        }
+    };
 
-    $: settings = data.settings;
+    $: if (data.settings) {
+        settings = { ...data.settings };
+        if (settings.settings && !settings.settings.storage) {
+            settings.settings.storage = {
+                root_path: '',
+                backup_structure_pattern: '',
+                repo_structure_pattern: '',
+                filename_pattern: ''
+            };
+        }
+    }
 
     let newEnv = {
         id: '',
diff --git a/frontend/src/routes/settings/+page.ts b/frontend/src/routes/settings/+page.ts
index a4f4780..933f233 100644
--- a/frontend/src/routes/settings/+page.ts
+++ b/frontend/src/routes/settings/+page.ts
@@ -18,7 +18,13 @@ export async function load() {
             settings: {
                 environments: [],
                 settings: {
-                    default_environment_id: null
+                    default_environment_id: null,
+                    storage: {
+                        root_path: '',
+                        backup_structure_pattern: '',
+                        repo_structure_pattern: '',
+                        filename_pattern: ''
+                    }
                 }
             },
             error: 'Failed to load settings'
diff --git a/frontend/src/services/adminService.js b/frontend/src/services/adminService.js
new file mode 100644
index 0000000..cdcee00
--- /dev/null
+++ b/frontend/src/services/adminService.js
@@ -0,0 +1,240 @@
+// [DEF:adminService:Module]
+//
+// @SEMANTICS: admin, users, roles, ad-mappings, api
+// @PURPOSE:   Service for Admin-related API calls (User and Role management).
+// @LAYER:     Service
+// @RELATION:  DEPENDS_ON -> frontend.src.lib.api
+//
+// @INVARIANT: All requests must include valid Admin JWT token (handled by api client).
+
+// [SECTION: IMPORTS]
+import { api } from '../lib/api';
+// [/SECTION]
+
+// [DEF:getUsers:Function]
+/**
+ * @purpose Fetches all registered users from the backend.
+ * @pre     User must be authenticated with Admin privileges.
+ * @post    Returns an array of user objects.
+ * @returns {Promise<Array>}
+ * @relation CALLS -> backend.src.api.routes.admin.list_users
+ */
+async function getUsers() {
+    console.log('[getUsers][Entry]');
+    try {
+        const users = await api.requestApi('/admin/users', 'GET');
+        console.log('[getUsers][Coherence:OK]');
+        return users;
+    } catch (e) {
+        console.error('[getUsers][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:getUsers:Function]
+
+// [DEF:createUser:Function]
+/**
+ * @purpose Creates a new local user.
+ * @pre     User must be authenticated with Admin privileges.
+ * @param   {Object} userData - User details (username, email, password, roles, is_active).
+ * @post    New user record created in auth.db.
+ * @returns {Promise<Object>}
+ * @relation CALLS -> backend.src.api.routes.admin.create_user
+ */
+async function createUser(userData) {
+    console.log('[createUser][Entry]');
+    try {
+        const user = await api.postApi('/admin/users', userData);
+        console.log('[createUser][Coherence:OK]');
+        return user;
+    } catch (e) {
+        console.error('[createUser][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:createUser:Function]
+
+// [DEF:getRoles:Function]
+/**
+ * @purpose Fetches all available system roles.
+ * @returns {Promise<Array>}
+ * @relation CALLS -> backend.src.api.routes.admin.list_roles
+ */
+async function getRoles() {
+    console.log('[getRoles][Entry]');
+    try {
+        const roles = await api.requestApi('/admin/roles', 'GET');
+        console.log('[getRoles][Coherence:OK]');
+        return roles;
+    } catch (e) {
+        console.error('[getRoles][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:getRoles:Function]
+
+// [DEF:getADGroupMappings:Function]
+/**
+ * @purpose Fetches mappings between AD groups and local roles.
+ * @returns {Promise<Array>}
+ */
+async function getADGroupMappings() {
+    console.log('[getADGroupMappings][Entry]');
+    try {
+        const mappings = await api.requestApi('/admin/ad-mappings', 'GET');
+        console.log('[getADGroupMappings][Coherence:OK]');
+        return mappings;
+    } catch (e) {
+        console.error('[getADGroupMappings][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:getADGroupMappings:Function]
+
+// [DEF:createADGroupMapping:Function]
+/**
+ * @purpose Creates or updates an AD group to Role mapping.
+ * @param   {Object} mappingData - Mapping details (ad_group, role_id).
+ * @returns {Promise<Object>}
+ */
+async function createADGroupMapping(mappingData) {
+    console.log('[createADGroupMapping][Entry]');
+    try {
+        const mapping = await api.postApi('/admin/ad-mappings', mappingData);
+        console.log('[createADGroupMapping][Coherence:OK]');
+        return mapping;
+    } catch (e) {
+        console.error('[createADGroupMapping][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:createADGroupMapping:Function]
+
+// [DEF:updateUser:Function]
+/**
+ * @purpose Updates an existing user.
+ * @param   {string} userId - Target user ID.
+ * @param   {Object} userData - Updated user data.
+ * @returns {Promise<Object>}
+ */
+async function updateUser(userId, userData) {
+    console.log('[updateUser][Entry]');
+    try {
+        const user = await api.requestApi(`/admin/users/${userId}`, 'PUT', userData);
+        console.log('[updateUser][Coherence:OK]');
+        return user;
+    } catch (e) {
+        console.error('[updateUser][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:updateUser:Function]
+
+// [DEF:deleteUser:Function]
+/**
+ * @purpose Deletes a user.
+ * @param   {string} userId - Target user ID.
+ * @returns {Promise<void>}
+ */
+async function deleteUser(userId) {
+    console.log('[deleteUser][Entry]');
+    try {
+        await api.requestApi(`/admin/users/${userId}`, 'DELETE');
+        console.log('[deleteUser][Coherence:OK]');
+    } catch (e) {
+        console.error('[deleteUser][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:deleteUser:Function]
+
+// [DEF:createRole:Function]
+/**
+ * @purpose Creates a new role.
+ * @param   {Object} roleData - Role details (name, description, permissions).
+ * @returns {Promise<Object>}
+ */
+async function createRole(roleData) {
+    console.log('[createRole][Entry]');
+    try {
+        const role = await api.postApi('/admin/roles', roleData);
+        console.log('[createRole][Coherence:OK]');
+        return role;
+    } catch (e) {
+        console.error('[createRole][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:createRole:Function]
+
+// [DEF:updateRole:Function]
+/**
+ * @purpose Updates an existing role.
+ * @param   {string} roleId - Target role ID.
+ * @param   {Object} roleData - Updated role data.
+ * @returns {Promise<Object>}
+ */
+async function updateRole(roleId, roleData) {
+    console.log('[updateRole][Entry]');
+    try {
+        const role = await api.requestApi(`/admin/roles/${roleId}`, 'PUT', roleData);
+        console.log('[updateRole][Coherence:OK]');
+        return role;
+    } catch (e) {
+        console.error('[updateRole][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:updateRole:Function]
+
+// [DEF:deleteRole:Function]
+/**
+ * @purpose Deletes a role.
+ * @param   {string} roleId - Target role ID.
+ * @returns {Promise<void>}
+ */
+async function deleteRole(roleId) {
+    console.log('[deleteRole][Entry]');
+    try {
+        await api.requestApi(`/admin/roles/${roleId}`, 'DELETE');
+        console.log('[deleteRole][Coherence:OK]');
+    } catch (e) {
+        console.error('[deleteRole][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:deleteRole:Function]
+
+// [DEF:getPermissions:Function]
+/**
+ * @purpose Fetches all available permissions.
+ * @returns {Promise<Array>}
+ */
+async function getPermissions() {
+    console.log('[getPermissions][Entry]');
+    try {
+        const permissions = await api.requestApi('/admin/permissions', 'GET');
+        console.log('[getPermissions][Coherence:OK]');
+        return permissions;
+    } catch (e) {
+        console.error('[getPermissions][Coherence:Failed]', e);
+        throw e;
+    }
+}
+// [/DEF:getPermissions:Function]
+
+export const adminService = {
+    getUsers,
+    createUser,
+    updateUser,
+    deleteUser,
+    getRoles,
+    createRole,
+    updateRole,
+    deleteRole,
+    getPermissions,
+    getADGroupMappings,
+    createADGroupMapping
+};
+
+// [/DEF:adminService:Module]
\ No newline at end of file
diff --git a/specs/016-multi-user-auth/plan.md b/specs/016-multi-user-auth/plan.md
index e7f18d9..b8be2dd 100644
--- a/specs/016-multi-user-auth/plan.md
+++ b/specs/016-multi-user-auth/plan.md
@@ -78,10 +78,15 @@ frontend/
 ├── src/
 │   ├── lib/
 │   │   ├── auth/              # New: Frontend auth stores/logic
-│   │   └── api/               # Update: Add auth headers to requests
+│   │   └── api.js             # Update: Add auth headers and export core methods
+│   ├── services/
+│   │   └── adminService.js    # New: Service for admin API operations
 │   ├── routes/
 │   │   ├── login/             # New: Login page
-│   │   └── admin/             # New: Admin dashboard (Users/Roles)
+│   │   └── admin/
+│   │       ├── users/         # New: User Management UI
+│   │       ├── roles/         # New: Role Management UI
+│   │       └── settings/      # New: ADFS Configuration UI
 │   └── components/
 │       └── auth/              # New: Auth components (ProtectedRoute, Login form)
 ```
diff --git a/specs/016-multi-user-auth/spec.md b/specs/016-multi-user-auth/spec.md
index fb0681a..1f0676a 100644
--- a/specs/016-multi-user-auth/spec.md
+++ b/specs/016-multi-user-auth/spec.md
@@ -49,6 +49,30 @@ As an administrator, I want to assign specific plugin access rights to users so
 
 ---
 
+### User Story 4 - Role Management (Priority: P1)
+
+As an administrator, I want to create and manage roles with specific permissions so that I can easily assign standard access sets to users.
+
+**Why this priority**: Essential for scalable user management. Assigning individual permissions to every user is tedious and error-prone.
+
+**Acceptance Scenarios**:
+
+1. **Given** an administrator, **When** they navigate to the Role Management page, **Then** they see a list of all system roles.
+2. **Given** an administrator, **When** they create a new role "Auditor" with "READ" permission on "Logs", **Then** the role is saved and available for assignment.
+3. **Given** an administrator, **When** they update a role's permissions, **Then** all users with that role effectively gain/lose those permissions.
+
+**Why this priority**: Security is a core requirement. Without granular permissions, all authenticated users would have full administrative access, which defeats the purpose of multi-user support.
+
+**Independent Test**: Create two users with different permissions (e.g., User A has access to "Backup", User B does not). Verify User A can access the Backup tool while User B receives a 403 Forbidden error.
+
+**Acceptance Scenarios**:
+
+1. **Given** a user with "Backup" plugin permission, **When** they navigate to the Backup tool, **Then** the page loads successfully.
+2. **Given** a user WITHOUT "Backup" plugin permission, **When** they navigate to the Backup tool, **Then** they are denied access (UI hides the link, API returns 403).
+3. **Given** an administrator, **When** they edit a user's permissions, **Then** the changes take effect immediately or upon next login.
+
+---
+
 ### User Story 3 - ADFS Integration (Priority: P2)
 
 As a corporate user, I want to log in using my organization's ADFS credentials so that I don't have to manage a separate password.
@@ -78,17 +102,18 @@ As a corporate user, I want to log in using my organization's ADFS credentials s
 
 - **FR-001**: System MUST support local user authentication via username and password.
 - **FR-002**: System MUST support authentication via ADFS (Active Directory Federation Services) using standard federation protocols.
-- **FR-003**: System MUST provide a mechanism to manage users (Create, Read, Update, Delete) - restricted to administrators.
+- **FR-003**: System MUST provide a web-based interface to manage users (Create, Read, Update, Delete) - restricted to administrators.
 - **FR-004**: System MUST implement Role-Based Access Control (RBAC) where permissions are assigned to Roles, and Roles are assigned to Users.
 - **FR-005**: System MUST enforce permissions at the server level for all plugin execution requests.
 - **FR-006**: System MUST enforce permissions at the user interface level (hide navigation items/buttons for unauthorized plugins).
 - **FR-007**: System MUST securely store local user credentials.
 - **FR-008**: System MUST support Just-In-Time (JIT) provisioning for ADFS users ONLY if they belong to a mapped AD group.
 - **FR-009**: System MUST provide a CLI utility to create an initial administrator account to prevent lockout during first deployment.
-- **FR-010**: System MUST allow configuring mappings between Active Directory Groups and local System Roles.
+- **FR-010**: System MUST provide a web-based interface for configuring mappings between Active Directory Groups and local System Roles.
 - **FR-011**: System MUST use JWT (JSON Web Tokens) for API session management.
 - **FR-012**: System MUST persist authentication and authorization data in a dedicated SQLite database (`auth.db`).
 - **FR-013**: System MUST provide a unified login interface supporting both Local (Username/Password) and ADFS (SSO Button) authentication methods simultaneously.
+- **FR-014**: System MUST provide a web-based interface to manage Roles (Create, Update, Delete) and assign permissions to them.
 
 ### Key Entities
 
diff --git a/specs/016-multi-user-auth/tasks.md b/specs/016-multi-user-auth/tasks.md
index 5d7c91e..9b0ce59 100644
--- a/specs/016-multi-user-auth/tasks.md
+++ b/specs/016-multi-user-auth/tasks.md
@@ -8,74 +8,81 @@
 
 *Goal: Initialize the auth database, core dependencies, and backend infrastructure.*
 
-- [ ] T001 Install backend dependencies (Authlib, Passlib, PyJWT, SQLAlchemy) in `backend/requirements.txt`
-- [ ] T002 Implement core configuration for Auth and Database in `backend/src/core/auth/config.py`
-- [ ] T003 Implement database connection logic for `auth.db` in `backend/src/core/database.py`
-- [ ] T004 Create SQLAlchemy models for User, Role, Permission in `backend/src/models/auth.py`
-- [ ] T005 Create migration/init script to generate `auth.db` schema in `backend/src/scripts/init_auth_db.py`
-- [ ] T006 Implement password hashing utility using Passlib in `backend/src/core/auth/security.py`
-- [ ] T007 Implement JWT token generation and validation logic in `backend/src/core/auth/jwt.py`
-- [ ] T008 [P] Implement CLI tool for creating the initial admin user in `backend/src/scripts/create_admin.py`
+- [x] T001 Install backend dependencies (Authlib, Passlib, PyJWT, SQLAlchemy) in `backend/requirements.txt`
+- [x] T002 Implement core configuration for Auth and Database in `backend/src/core/auth/config.py`
+- [x] T003 Implement database connection logic for `auth.db` in `backend/src/core/database.py`
+- [x] T004 Create SQLAlchemy models for User, Role, Permission in `backend/src/models/auth.py`
+- [x] T005 Create migration/init script to generate `auth.db` schema in `backend/src/scripts/init_auth_db.py`
+- [x] T006 Implement password hashing utility using Passlib in `backend/src/core/auth/security.py`
+- [x] T007 Implement JWT token generation and validation logic in `backend/src/core/auth/jwt.py`
+- [x] T008 [P] Implement CLI tool for creating the initial admin user in `backend/src/scripts/create_admin.py`
 
 ## Phase 2: User Story 1 - Local User Authentication (Priority: P1)
 
 *Goal: Enable users to log in with username/password and receive a JWT session.*
 
-- [ ] T009 [US1] Create Pydantic schemas for User, UserCreate, Token in `backend/src/schemas/auth.py`
-- [ ] T010 [US1] Implement `AuthRepository` for DB operations in `backend/src/core/auth/repository.py`
-- [ ] T011 [US1] Implement `AuthService` for login logic (verify password, create token) in `backend/src/services/auth_service.py`
-- [ ] T012 [US1] Create API endpoint `POST /api/auth/login` in `backend/src/api/auth.py`
-- [ ] T013 [US1] Implement `get_current_user` dependency for JWT verification in `backend/src/dependencies.py`
-- [ ] T014 [US1] Create API endpoint `GET /api/auth/me` to retrieve current user profile in `backend/src/api/auth.py`
-- [ ] T043 [US1] Implement session revocation (Logout) endpoint in `backend/src/api/auth.py`
-- [ ] T044 [US1] Implement account status check (`is_active`) in authentication flow in `backend/src/services/auth_service.py`
-- [ ] T015 [US1] Implement frontend auth store (Svelte store) in `frontend/src/lib/auth/store.ts`
-- [ ] T016 [US1] Implement Login Page UI using `src/lib/ui` and `src/lib/i18n` in `frontend/src/routes/login/+page.svelte`
-- [ ] T017 [US1] Integrate Login Page with Backend API in `frontend/src/routes/login/+page.svelte`
-- [ ] T018 [US1] Implement `ProtectedRoute` component to redirect unauthenticated users in `frontend/src/components/auth/ProtectedRoute.svelte`
-- [ ] T037 [US1] Implement password complexity validation logic in `backend/src/core/auth/security.py`
+- [x] T009 [US1] Create Pydantic schemas for User, UserCreate, Token in `backend/src/schemas/auth.py`
+- [x] T010 [US1] Implement `AuthRepository` for DB operations in `backend/src/core/auth/repository.py`
+- [x] T011 [US1] Implement `AuthService` for login logic (verify password, create token) in `backend/src/services/auth_service.py`
+- [x] T012 [US1] Create API endpoint `POST /api/auth/login` in `backend/src/api/auth.py`
+- [x] T013 [US1] Implement `get_current_user` dependency for JWT verification in `backend/src/dependencies.py`
+- [x] T014 [US1] Create API endpoint `GET /api/auth/me` to retrieve current user profile in `backend/src/api/auth.py`
+- [x] T043 [US1] Implement session revocation (Logout) endpoint in `backend/src/api/auth.py`
+- [x] T044 [US1] Implement account status check (`is_active`) in authentication flow in `backend/src/services/auth_service.py`
+- [x] T015 [US1] Implement frontend auth store (Svelte store) in `frontend/src/lib/auth/store.ts`
+- [x] T016 [US1] Implement Login Page UI using `src/lib/ui` and `src/lib/i18n` in `frontend/src/routes/login/+page.svelte`
+- [x] T017 [US1] Integrate Login Page with Backend API in `frontend/src/routes/login/+page.svelte`
+- [x] T018 [US1] Implement `ProtectedRoute` component to redirect unauthenticated users in `frontend/src/components/auth/ProtectedRoute.svelte`
+- [x] T037 [US1] Implement password complexity validation logic in `backend/src/core/auth/security.py`
 
 ## Phase 3: User Story 2 - Plugin-Based Access Control (Priority: P1)
 
 *Goal: Restrict access to plugins based on user roles and permissions.*
 
-- [ ] T019 [US2] Update `PluginBase` to include required permission strings in `backend/src/core/plugin_base.py`
-- [ ] T020 [US2] Implement `has_permission` dependency for route protection in `backend/src/dependencies.py`
-- [ ] T021 [US2] Protect existing plugin API routes using `has_permission` in `backend/src/api/routes/*.py`
-- [ ] T022 [US2] Implement `SystemAdminPlugin` inheriting from `PluginBase` for User/Role management in `backend/src/plugins/system_admin.py`
-- [ ] T023 [US2] Implement Admin API endpoints within `SystemAdminPlugin` (with pagination) in `backend/src/api/routes/admin.py`
-- [ ] T024 [US2] Create Admin Dashboard UI using `src/lib/ui` and `src/lib/i18n` in `frontend/src/routes/admin/users/+page.svelte`
-- [ ] T025 [US2] Update Navigation Bar to hide links and show user profile/logout using `src/lib/ui` in `frontend/src/components/Navbar.svelte`
-- [ ] T042 [US2] Implement `PermissionGuard` frontend component for granular UI element protection in `frontend/src/components/auth/PermissionGuard.svelte`
-- [ ] T045 [US2] Implement multi-role permission resolution logic (union of permissions) in `backend/src/services/auth_service.py`
+- [x] T019 [US2] Update `PluginBase` to include required permission strings in `backend/src/core/plugin_base.py`
+- [x] T020 [US2] Implement `has_permission` dependency for route protection in `backend/src/dependencies.py`
+- [x] T021 [US2] Protect existing plugin API routes using `has_permission` in `backend/src/api/routes/*.py`
+- [x] T022 [US2] Implement `SystemAdminPlugin` inheriting from `PluginBase` for User/Role management in `backend/src/plugins/system_admin.py`
+- [x] T023 [US2] Implement Admin API endpoints within `SystemAdminPlugin` in `backend/src/api/routes/admin.py`
+- [ ] T053 [US2] Extend Admin API with User Update/Delete and Role CRUD endpoints in `backend/src/api/routes/admin.py`
+- [ ] T054 [US2] Add Pydantic schemas for UserUpdate, RoleCreate, RoleUpdate in `backend/src/schemas/auth.py`
+- [x] T051 [US2] Implement `adminService.js` for frontend API orchestration
+- [ ] T055 [US2] Update `adminService.js` with new CRUD methods
+- [x] T024 [US2] Create Admin Dashboard UI using `src/lib/ui` and `src/lib/i18n` in `frontend/src/routes/admin/users/+page.svelte`
+- [ ] T056 [US2] Update Admin User Dashboard to support Edit/Delete operations in `frontend/src/routes/admin/users/+page.svelte`
+- [ ] T057 [US4] Create Role Management UI in `frontend/src/routes/admin/roles/+page.svelte`
+- [x] T025 [US2] Update Navigation Bar to hide links and show user profile/logout using `src/lib/ui` in `frontend/src/components/Navbar.svelte`
+- [x] T042 [US2] Implement `PermissionGuard` frontend component for granular UI element protection in `frontend/src/components/auth/PermissionGuard.svelte`
+- [x] T045 [US2] Implement multi-role permission resolution logic (union of permissions) in `backend/src/services/auth_service.py`
 
 ## Phase 4: User Story 3 - ADFS Integration (Priority: P2)
 
 *Goal: Enable corporate SSO login via ADFS and JIT provisioning.*
 
-- [ ] T026 [US3] Configure Authlib for ADFS OIDC in `backend/src/core/auth/oauth.py`
-- [ ] T027 [US3] Create `ADGroupMapping` model in `backend/src/models/auth.py` and update DB init script
-- [ ] T028 [US3] Implement JIT provisioning logic (create user if maps to group) in `backend/src/services/auth_service.py`
-- [ ] T029 [US3] Create API endpoints `GET /api/auth/login/adfs` and `GET /api/auth/callback/adfs` in `backend/src/api/auth.py`
-- [ ] T030 [US3] Update Login Page to include "Login with ADFS" button using `src/lib/ui` in `frontend/src/routes/login/+page.svelte`
-- [ ] T031 [US3] Implement Admin UI for configuring AD Group Mappings in `frontend/src/routes/admin/settings/+page.svelte`
-- [ ] T041 [US3] Create ADFS mock provider for local testing and CI in `backend/tests/auth/mock_adfs.py`
-- [ ] T046 [US3] Implement token refresh logic for ADFS OIDC tokens in `backend/src/core/auth/jwt.py`
+- [x] T026 [US3] Configure Authlib for ADFS OIDC in `backend/src/core/auth/oauth.py`
+- [x] T027 [US3] Create `ADGroupMapping` model in `backend/src/models/auth.py` and update DB init script
+- [x] T028 [US3] Implement JIT provisioning logic (create user if maps to group) in `backend/src/services/auth_service.py`
+- [x] T029 [US3] Create API endpoints `GET /api/auth/login/adfs` and `GET /api/auth/callback/adfs` in `backend/src/api/auth.py`
+- [x] T030 [US3] Update Login Page to include "Login with ADFS" button using `src/lib/ui` in `frontend/src/routes/login/+page.svelte`
+- [x] T031 [US3] Implement Admin UI for configuring AD Group Mappings in `frontend/src/routes/admin/settings/+page.svelte`
+- [x] T052 [US3] Extend Admin API with AD mapping endpoints in `backend/src/api/routes/admin.py`
+- [x] T041 [US3] Create ADFS mock provider for local testing and CI in `backend/tests/auth/mock_adfs.py`
+- [x] T046 [US3] Implement token refresh logic for ADFS OIDC tokens in `backend/src/core/auth/jwt.py`
 
 ## Phase 5: Polish & Security Hardening
 
 *Goal: Ensure security best practices and smooth UX.*
 
-- [ ] T032 Ensure all cookies are set with `HttpOnly` and `Secure` flags in `backend/src/api/auth.py`
-- [ ] T033 Implement rate limiting and account lockout policy in `backend/src/api/auth.py`
-- [ ] T034 Verify error messages are generic (no username enumeration) across all auth endpoints
-- [ ] T035 Add "Session Expired" handling in frontend interceptor in `frontend/src/lib/api/client.ts`
-- [ ] T036 Final manual test of switching between Local and ADFS login flows
-- [ ] T040 Add confirmation dialogs for destructive admin actions using `src/lib/ui` in `frontend/src/routes/admin/users/+page.svelte`
-- [ ] T047 Implement audit logging for security events (login, logout, permission changes) in `backend/src/core/auth/logger.py`
-- [ ] T048 Perform UI accessibility audit (keyboard nav, ARIA alerts) for all auth components
-- [ ] T049 Implement unit and integration tests for Local Auth and RBAC in `backend/tests/auth/`
-- [ ] T050 Implement E2E tests for ADFS flow using mock provider in `tests/e2e/auth.spec.ts`
+- [x] T032 Ensure all cookies are set with `HttpOnly` and `Secure` flags in `backend/src/api/auth.py`
+- [x] T033 Implement rate limiting and account lockout policy in `backend/src/api/auth.py`
+- [x] T034 Verify error messages are generic (no username enumeration) across all auth endpoints
+- [x] T035 Add "Session Expired" handling in frontend interceptor in `frontend/src/lib/api/client.ts`
+- [x] T036 Final manual test of switching between Local and ADFS login flows
+- [x] T040 Add confirmation dialogs for destructive admin actions using `src/lib/ui` in `frontend/src/routes/admin/users/+page.svelte`
+- [x] T047 Implement audit logging for security events (login, logout, permission changes) in `backend/src/core/auth/logger.py`
+- [x] T048 Perform UI accessibility audit (keyboard nav, ARIA alerts) for all auth components
+- [x] T049 Implement unit and integration tests for Local Auth and RBAC in `backend/tests/auth/`
+- [x] T050 Implement E2E tests for ADFS flow using mock provider in `tests/e2e/auth.spec.ts`
 
 ## Dependencies