diff --git a/README.md b/README.md
index 43e153d..3b1b5cd 100644
--- a/README.md
+++ b/README.md
@@ -247,6 +247,8 @@ POST   /auth/password-reset          # Reset password with token
 POST   /auth/verify-email-request    # Request email verification
 POST   /auth/verify-email            # Verify email with token
 GET    /auth/me                      # Get current user info
+PATCH  /auth/me                      # Update own profile
+PATCH  /auth/users/{user_id}         # Update user profile (by admin)
 ```
 
 ### Error Handling
@@ -356,3 +358,4 @@ MIT
 
 * 0.1.0 - Initial Release
 * 0.2.0 - Added admin user auto creation
+* 0.2.1 - Added user profile update (PATCH on /me and /users/{user_id})
diff --git a/pyproject.toml b/pyproject.toml
index 621213b..9fa79fe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,7 +7,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "myauth"
-version = "0.2.0"
+version = "0.2.1"
 description = "A reusable, modular authentication system for FastAPI applications with pluggable database backends."
 readme = "README.md"
 authors = [
diff --git a/src/myauth/api/routes.py b/src/myauth/api/routes.py
index f71743c..bbafa11 100644
--- a/src/myauth/api/routes.py
+++ b/src/myauth/api/routes.py
@@ -4,7 +4,6 @@ FastAPI routes for authentication module.
 This module provides ready-to-use FastAPI routes for all authentication
 operations. Routes are organized in an APIRouter with /auth prefix.
 """
-import os
 from typing import Annotated
 
 from fastapi import Depends, HTTPException, status, FastAPI
@@ -18,7 +17,7 @@ from ..models.email_verification import (
   PasswordResetConfirm
 )
 from ..models.token import AccessTokenResponse, RefreshTokenRequest
-from ..models.user import UserCreate, UserResponse
+from ..models.user import UserCreate, UserResponse, UserUpdate, UserUpdateMe
 
 # OAuth2 scheme for token authentication
 oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/auth/login")
@@ -86,6 +85,35 @@ def create_auth_app(auth_service: AuthService) -> FastAPI:
         detail=e.message
       )
   
+  def get_current_admin(current_user: Annotated[UserResponse, Depends(get_current_user)]) -> UserResponse:
+    """
+    Dependency to ensure the current user has admin role.
+
+    This dependency can be used in any route that requires admin privileges.
+    It first validates the user's token (via get_current_user) then checks
+    for the 'admin' role.
+
+    Args:
+        current_user: The authenticated user (injected by get_current_user dependency).
+
+    Returns:
+        The current authenticated admin user.
+
+    Raises:
+        HTTPException: 403 if user does not have admin role.
+
+    Example:
+        >>> @auth_app.patch("/users/{user_id}")
+        >>> def update_user(user_id: str, admin: UserResponse = Depends(get_current_admin)):
+        >>>     # Only admins can access this route
+    """
+    if "admin" not in current_user.roles:
+      raise HTTPException(
+        status_code=status.HTTP_403_FORBIDDEN,
+        detail="Admin privileges required"
+      )
+    return current_user
+  
   @auth_app.post(
     "/register",
     response_model=UserResponse,
@@ -375,6 +403,123 @@ def create_auth_app(auth_service: AuthService) -> FastAPI:
         HTTPException: 401 if token is invalid or expired.
     """
     return current_user
+  
+  @auth_app.patch(
+    "/me",
+    response_model=UserResponse,
+    summary="Update own profile",
+    description="Update the current user's profile (restricted fields)."
+  )
+  def update_me(
+      updates: UserUpdateMe,
+      current_user: Annotated[UserResponse, Depends(get_current_user)]
+  ) -> UserResponse:
+    """
+    Update the current authenticated user's profile.
 
+    This endpoint allows users to update their own profile with restrictions:
+    - Allowed fields: email, username, password, user_settings
+    - Forbidden fields: roles, is_active, is_verified (must use other flows)
+
+    When changing password, the current session is preserved if refresh_token
+    is provided in the request body.
+
+    Args:
+        updates: User update data (restricted fields only).
+        current_user: The authenticated user (injected by dependency).
+
+    Returns:
+        Updated user information.
+
+    Raises:
+        HTTPException: 409 if new email already exists.
+        HTTPException: 422 if validation fails.
+    """
+    try:
+      # Convert UserUpdateMe to UserUpdate (only allowed fields)
+      from ..models.user import UserUpdate
+      
+      user_update = UserUpdate(
+        email=updates.email,
+        username=updates.username,
+        password=updates.password,
+        user_settings=updates.user_settings
+      )
+      
+      # Update user with optional refresh_token to preserve session
+      updated_user = auth_service.update_user(
+        user_id=current_user.id,
+        updates=user_update,
+        refresh_token=updates.refresh_token
+      )
+      
+      return UserResponse(
+        id=updated_user.id,
+        email=updated_user.email,
+        username=updated_user.username,
+        roles=updated_user.roles,
+        user_settings=updated_user.user_settings,
+        created_at=updated_user.created_at,
+        updated_at=updated_user.updated_at
+      )
+    except AuthError as e:
+      raise HTTPException(
+        status_code=e.status_code,
+        detail=e.message
+      )
+  
+  @auth_app.patch(
+    "/users/{user_id}",
+    response_model=UserResponse,
+    summary="Update any user (admin only)",
+    description="Update any user's profile with full access to all fields (admin only)."
+  )
+  def update_user_by_id(
+      user_id: str,
+      updates: UserUpdate,
+      admin: Annotated[UserResponse, Depends(get_current_admin)]
+  ) -> UserResponse:
+    """
+    Update any user's profile (admin only).
+
+    This endpoint allows administrators to update any user with full access
+    to all fields including roles, is_active, and is_verified.
+
+    Args:
+        user_id: The ID of the user to update.
+        updates: User update data (all fields allowed).
+        admin: The authenticated admin user (injected by dependency).
+
+    Returns:
+        Updated user information.
+
+    Raises:
+        HTTPException: 403 if user is not an admin.
+        HTTPException: 404 if user not found.
+        HTTPException: 409 if new email already exists.
+        HTTPException: 422 if validation fails.
+    """
+    try:
+      # Admin updates don't preserve refresh tokens (security)
+      updated_user = auth_service.update_user(
+        user_id=user_id,
+        updates=updates,
+        refresh_token=None
+      )
+      
+      return UserResponse(
+        id=updated_user.id,
+        email=updated_user.email,
+        username=updated_user.username,
+        roles=updated_user.roles,
+        user_settings=updated_user.user_settings,
+        created_at=updated_user.created_at,
+        updated_at=updated_user.updated_at
+      )
+    except AuthError as e:
+      raise HTTPException(
+        status_code=e.status_code,
+        detail=e.message
+      )
   
   return auth_app
diff --git a/src/myauth/core/auth.py b/src/myauth/core/auth.py
index 2fde4e5..fdcf2e7 100644
--- a/src/myauth/core/auth.py
+++ b/src/myauth/core/auth.py
@@ -18,7 +18,7 @@ from ..exceptions import (
   AccountDisabledError,
   ExpiredTokenError,
   InvalidTokenError,
-  RevokedTokenError
+  RevokedTokenError, UserAlreadyExistsError
 )
 from ..models.token import AccessTokenResponse, TokenData
 from ..models.user import UserCreate, UserInDB, UserUpdate, UserCreateNoValidation
@@ -512,3 +512,61 @@ class AuthService:
     :rtype: list
     """
     return self.user_repository.list_users(skip, limit)
+  
+  def update_user(self, user_id: str, updates: UserUpdate, refresh_token: Optional[str] = None) -> UserInDB:
+    """
+    Update an existing user's information.
+
+    This method handles user profile updates with automatic security measures:
+    - Validates email uniqueness if email is changed
+    - Automatically sets is_verified=False if email is changed
+    - Hashes password if provided
+    - Revokes refresh tokens (except current one) if password is changed
+
+    Args:
+        user_id: The unique user identifier.
+        updates: Pydantic model containing fields to update.
+        refresh_token: Optional current refresh token to preserve when password changes.
+
+    Returns:
+        The updated user.
+
+    Raises:
+        UserNotFoundError: If user does not exist.
+        UserAlreadyExistsError: If new email is already used by another user.
+
+    Example:
+        >>> updates = UserUpdate(email="newemail@example.com")
+        >>> user = auth_service.update_user(user_id, updates)
+        >>>
+        >>> # Update password while preserving current session
+        >>> updates = UserUpdate(password="NewSecurePass123!")
+        >>> user = auth_service.update_user(user_id, updates, refresh_token=current_token)
+    """
+    # Get current user to compare changes
+    current_user = self.user_repository.get_user_by_id(user_id)
+    if not current_user:
+      raise UserNotFoundError(f"User with id {user_id} not found")
+    
+    # Handle email change
+    if updates.email is not None and updates.email != current_user.email:
+      # Check if new email is already used by another user
+      if self.user_repository.email_exists(updates.email):
+        raise UserAlreadyExistsError(f"Email {updates.email} is already in use")
+      
+      # Force email verification to false when email changes
+      updates.is_verified = False
+    
+    # Handle password change
+    if updates.password is not None:
+      # Hash the new password
+      hashed_password = self.password_manager.hash_password(updates.password)
+      updates.password = hashed_password
+      
+      # Revoke all refresh tokens except the current one (if provided)
+      self.token_repository.revoke_all_user_tokens(user_id, "refresh", except_token=refresh_token)
+    
+    # Update user in database
+    updated_user = self.user_repository.update_user(user_id, updates)
+    
+    return updated_user
\ No newline at end of file
diff --git a/src/myauth/models/user.py b/src/myauth/models/user.py
index f5240ee..7353bf3 100644
--- a/src/myauth/models/user.py
+++ b/src/myauth/models/user.py
@@ -153,6 +153,67 @@ class UserUpdate(BaseModel):
     Raises:
         ValueError: If username is provided but empty or too long.
     """
+    if value is None:
+      return None
+    return validate_username_not_empty(value)
+
+
+class UserUpdateMe(BaseModel):
+  """
+  Model for user self-update (restricted fields).
+
+  This model allows users to update their own profile with restrictions:
+  - Allowed fields: email, username, password, user_settings
+  - Forbidden fields: roles, is_active, is_verified
+  - Optional refresh_token to preserve current session when changing password
+
+  Attributes:
+      email: Optional new email address.
+      username: Optional new username.
+      password: Optional new password (will be hashed and validated).
+      user_settings: Optional new settings dict.
+      refresh_token: Optional refresh token to preserve when changing password.
+  """
+  email: Optional[EmailStr] = None
+  username: Optional[str] = None
+  password: Optional[str] = None
+  user_settings: Optional[dict] = None
+  refresh_token: Optional[str] = None
+  
+  @field_validator('password')
+  @classmethod
+  def validate_password_strength(cls, value: Optional[str]) -> Optional[str]:
+    """
+    Validate password meets security requirements if provided.
+
+    Args:
+        value: The password to validate (can be None).
+
+    Returns:
+        The validated password or None.
+
+    Raises:
+        ValueError: If password is provided but does not meet security requirements.
+    """
+    return validate_password_strength(value)
+  
+  @field_validator('username')
+  @classmethod
+  def validate_username(cls, value: Optional[str]) -> Optional[str]:
+    """
+    Validate username if provided.
+
+    Args:
+        value: The username to validate (can be None).
+
+    Returns:
+        The validated username or None.
+
+    Raises:
+        ValueError: If username is provided but empty or too long.
+    """
+    if value is None:
+      return None
     return validate_username_not_empty(value)
 
 
diff --git a/src/myauth/persistence/base.py b/src/myauth/persistence/base.py
index da101f8..0da7edd 100644
--- a/src/myauth/persistence/base.py
+++ b/src/myauth/persistence/base.py
@@ -8,6 +8,7 @@ PostgreSQL, custom engines, etc.).
 """
 
 from abc import ABC, abstractmethod
+from typing import Optional
 
 from ..models.token import TokenData
 from ..models.user import UserCreate, UserInDB, UserUpdate
@@ -203,16 +204,19 @@ class TokenRepository(ABC):
     pass
   
   @abstractmethod
-  def revoke_all_user_tokens(self, user_id: str, token_type: str) -> int:
+  def revoke_all_user_tokens(self, user_id: str, token_type: str, except_token: Optional[str] = None) -> int:
     """
     Revoke all tokens of a specific type for a user.
 
     This is useful for logout-all-devices functionality or when a user's
-    password is changed (invalidating all refresh tokens).
+    password is changed (invalidating all refresh tokens). Optionally,
+    a specific token can be excluded from revocation to preserve the
+    current session.
 
     Args:
         user_id: The user whose tokens should be revoked.
         token_type: Type of tokens to revoke ("refresh" or "password_reset").
+        except_token: Optional token string to exclude from revocation.
 
     Returns:
         Number of tokens revoked.
diff --git a/src/myauth/persistence/sqlite.py b/src/myauth/persistence/sqlite.py
index 9f39e4a..8396479 100644
--- a/src/myauth/persistence/sqlite.py
+++ b/src/myauth/persistence/sqlite.py
@@ -13,9 +13,9 @@ from typing import Optional
 from uuid import uuid4
 
 from .base import UserRepository, TokenRepository
-from ..models.user import UserCreate, UserInDB, UserUpdate
-from ..models.token import TokenData
 from ..exceptions import UserAlreadyExistsError, UserNotFoundError
+from ..models.token import TokenData
+from ..models.user import UserCreate, UserInDB, UserUpdate
 
 
 class SQLiteUserRepository(UserRepository):
@@ -364,38 +364,38 @@ class SQLiteUserRepository(UserRepository):
       cursor = conn.cursor()
       cursor.execute("SELECT 1 FROM users WHERE email = ? LIMIT 1", (email,))
       return cursor.fetchone() is not None
-    
+  
   def list_users(self, skip: int = 0, limit: int = 100) -> list[UserInDB]:
-      """
-      List users with pagination.
+    """
+    List users with pagination.
 
-      Args:
-          skip: Number of users to skip (default: 0).
-          limit: Maximum number of users to return (default: 100).
+    Args:
+        skip: Number of users to skip (default: 0).
+        limit: Maximum number of users to return (default: 100).
 
-      Returns:
-          List of users.
-      """
-      with sqlite3.connect(self.db_path) as conn:
-        cursor = conn.cursor()
-        cursor.execute("""
-                       SELECT id,
-                              email,
-                              username,
-                              hashed_password,
-                              roles,
-                              user_settings,
-                              is_verified,
-                              is_active,
-                              created_at,
-                              updated_at
-                       FROM users
-                       ORDER BY created_at DESC LIMIT ?
-                       OFFSET ?
-                       """, (limit, skip))
-        
-        rows = cursor.fetchall()
-        return [self._row_to_user(row) for row in rows]
+    Returns:
+        List of users.
+    """
+    with sqlite3.connect(self.db_path) as conn:
+      cursor = conn.cursor()
+      cursor.execute("""
+                     SELECT id,
+                            email,
+                            username,
+                            hashed_password,
+                            roles,
+                            user_settings,
+                            is_verified,
+                            is_active,
+                            created_at,
+                            updated_at
+                     FROM users
+                     ORDER BY created_at DESC LIMIT ?
+                     OFFSET ?
+                     """, (limit, skip))
+      
+      rows = cursor.fetchall()
+      return [self._row_to_user(row) for row in rows]
   
   def count_users(self) -> int:
     """
@@ -410,6 +410,7 @@ class SQLiteUserRepository(UserRepository):
       result = cursor.fetchone()
       return result[0] if result else 0
 
+
 class SQLiteTokenRepository(TokenRepository):
   """
   SQLite implementation of TokenRepository.
@@ -589,25 +590,44 @@ class SQLiteTokenRepository(TokenRepository):
       conn.commit()
       return cursor.rowcount > 0
   
-  def revoke_all_user_tokens(self, user_id: str, token_type: str) -> int:
+  def revoke_all_user_tokens(self, user_id: str, token_type: str, except_token: Optional[str] = None) -> int:
     """
     Revoke all tokens of a specific type for a user.
 
+    This is useful for logout-all-devices functionality or when a user's
+    password is changed (invalidating all refresh tokens). Optionally,
+    a specific token can be excluded from revocation to preserve the
+    current session.
+
     Args:
         user_id: The user whose tokens should be revoked.
-        token_type: Type of tokens to revoke.
+        token_type: Type of tokens to revoke ("refresh" or "password_reset").
+        except_token: Optional token string to exclude from revocation.
 
     Returns:
         Number of tokens revoked.
     """
     with sqlite3.connect(self.db_path) as conn:
       cursor = conn.cursor()
-      cursor.execute("""
-                     UPDATE tokens
-                     SET is_revoked = 1
-                     WHERE user_id = ?
-                       AND token_type = ?
-                     """, (user_id, token_type))
+      
+      if except_token is not None:
+        # Revoke all tokens except the specified one
+        cursor.execute("""
+                       UPDATE tokens
+                       SET is_revoked = 1
+                       WHERE user_id = ?
+                         AND token_type = ?
+                         AND token != ?
+                       """, (user_id, token_type, except_token))
+      else:
+        # Revoke all tokens
+        cursor.execute("""
+                       UPDATE tokens
+                       SET is_revoked = 1
+                       WHERE user_id = ?
+                         AND token_type = ?
+                       """, (user_id, token_type))
+      
       conn.commit()
       return cursor.rowcount
   
@@ -652,4 +672,4 @@ class SQLiteTokenRepository(TokenRepository):
     if token_data.expires_at < datetime.now():
       return False
     
-    return True
\ No newline at end of file
+    return True
diff --git a/tests/api/test_api_routes.py b/tests/api/test_api_routes.py
index af75640..3e283eb 100644
--- a/tests/api/test_api_routes.py
+++ b/tests/api/test_api_routes.py
@@ -513,3 +513,361 @@ def test_i_cannot_access_protected_route_with_invalid_token(client, mock_auth_se
   )
   
   assert response.status_code == 401
+
+
+def test_i_can_update_my_email(client, mock_auth_service, sample_user):
+  """
+  Test user can update their own email.
+
+  Verifies that a PATCH request to /auth/me with a new email
+  successfully updates the user's email address.
+  """
+  updated_user = sample_user.model_copy(update={"email": "newemail@example.com"})
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={"email": "newemail@example.com"}
+  )
+  
+  assert response.status_code == 200
+  data = response.json()
+  assert data["email"] == "newemail@example.com"
+  mock_auth_service.update_user.assert_called_once()
+
+
+def test_i_can_update_my_username(client, mock_auth_service, sample_user):
+  """
+  Test user can update their own username.
+
+  Verifies that a PATCH request to /auth/me with a new username
+  successfully updates the user's username.
+  """
+  updated_user = sample_user.model_copy(update={"username": "newusername"})
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={"username": "newusername"}
+  )
+  
+  assert response.status_code == 200
+  data = response.json()
+  assert data["username"] == "newusername"
+  mock_auth_service.update_user.assert_called_once()
+
+
+def test_i_can_update_my_password(client, mock_auth_service, sample_user):
+  """
+  Test user can update their own password.
+
+  Verifies that a PATCH request to /auth/me with a new password
+  successfully updates the password (which will be hashed by the service).
+  """
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.return_value = sample_user
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={"password": "NewSecurePass123!"}
+  )
+  
+  assert response.status_code == 200
+  mock_auth_service.update_user.assert_called_once()
+  # Verify password was included in the update
+  call_args = mock_auth_service.update_user.call_args
+  assert call_args[1]["updates"].password == "NewSecurePass123!"
+
+
+def test_i_can_update_my_password_and_preserve_session(client, mock_auth_service, sample_user):
+  """
+  Test user can update password while preserving current session.
+
+  Verifies that when a refresh_token is provided in the request body,
+  it is passed to the service to preserve the current session.
+  """
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.return_value = sample_user
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={
+        "password": "NewSecurePass123!",
+        "refresh_token": "current_refresh_token"
+    }
+  )
+  
+  assert response.status_code == 200
+  mock_auth_service.update_user.assert_called_once()
+  # Verify refresh_token was passed to preserve session
+  call_args = mock_auth_service.update_user.call_args
+  assert call_args[1]["refresh_token"] == "current_refresh_token"
+
+
+def test_i_can_update_my_user_settings(client, mock_auth_service, sample_user):
+  """
+  Test user can update their own settings.
+
+  Verifies that a PATCH request to /auth/me with new user_settings
+  successfully updates the user's custom settings.
+  """
+  new_settings = {"theme": "dark", "language": "fr", "notifications": True}
+  updated_user = sample_user.model_copy(update={"user_settings": new_settings})
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={"user_settings": new_settings}
+  )
+  
+  assert response.status_code == 200
+  data = response.json()
+  assert data["user_settings"] == new_settings
+  mock_auth_service.update_user.assert_called_once()
+
+
+def test_i_can_update_multiple_fields_on_my_profile(client, mock_auth_service, sample_user):
+  """
+  Test user can update multiple fields simultaneously.
+
+  Verifies that a PATCH request to /auth/me can update multiple
+  fields (email, username, user_settings) at once.
+  """
+  updated_user = sample_user.model_copy(update={
+      "email": "multiemail@example.com",
+      "username": "multiuser",
+      "user_settings": {"theme": "light"}
+  })
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={
+        "email": "multiemail@example.com",
+        "username": "multiuser",
+        "user_settings": {"theme": "light"}
+    }
+  )
+  
+  assert response.status_code == 200
+  data = response.json()
+  assert data["email"] == "multiemail@example.com"
+  assert data["username"] == "multiuser"
+  assert data["user_settings"] == {"theme": "light"}
+  mock_auth_service.update_user.assert_called_once()
+
+
+def test_i_cannot_update_my_profile_without_authentication(client):
+  """
+  Test updating profile fails without authentication.
+
+  Verifies that a PATCH request to /auth/me without a Bearer token
+  returns 401 Unauthorized status.
+  """
+  response = client.patch(
+    "/auth/me",
+    json={"username": "shouldfail"}
+  )
+  
+  assert response.status_code == 401
+
+
+def test_i_cannot_update_my_email_to_existing_email(client, mock_auth_service, sample_user):
+  """
+  Test updating email fails if already exists.
+
+  Verifies that attempting to update email to an already registered
+  email returns 409 Conflict status.
+  """
+  mock_auth_service.get_current_user.return_value = sample_user
+  mock_auth_service.update_user.side_effect = UserAlreadyExistsError(
+    "Email already in use"
+  )
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer sample.access.token"},
+    json={"email": "existing@example.com"}
+  )
+  
+  assert response.status_code == 409
+  assert "already" in response.json()["detail"].lower()
+
+
+def test_i_cannot_update_my_profile_with_invalid_token(client, mock_auth_service):
+  """
+  Test updating profile fails with invalid token.
+
+  Verifies that attempting to access /auth/me with an invalid token
+  returns 401 Unauthorized status.
+  """
+  mock_auth_service.get_current_user.side_effect = InvalidTokenError(
+    "Invalid access token"
+  )
+  
+  response = client.patch(
+    "/auth/me",
+    headers={"Authorization": "Bearer invalid.token"},
+    json={"username": "shouldfail"}
+  )
+  
+  assert response.status_code == 401
+
+
+def test_admin_can_update_any_user(client, mock_auth_service, sample_user):
+  """
+  Test admin can update any user.
+
+  Verifies that an admin can successfully update another user's
+  information via PATCH /auth/users/{user_id}.
+  """
+  admin_user = sample_user.model_copy(update={"roles": ["admin"]})
+  target_user = sample_user.model_copy(update={"id": "target_user_id", "username": "targetuser"})
+  updated_user = target_user.model_copy(update={"username": "updatedusername"})
+  
+  mock_auth_service.get_current_user.return_value = admin_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/users/target_user_id",
+    headers={"Authorization": "Bearer admin.access.token"},
+    json={"username": "updatedusername"}
+  )
+  
+  assert response.status_code == 200
+  data = response.json()
+  assert data["username"] == "updatedusername"
+  mock_auth_service.update_user.assert_called_once()
+
+
+def test_admin_can_update_user_roles(client, mock_auth_service, sample_user):
+  """
+  Test admin can update user roles.
+
+  Verifies that an admin can change a user's roles, which is forbidden
+  for regular users on the /auth/me endpoint.
+  """
+  admin_user = sample_user.model_copy(update={"roles": ["admin"]})
+  target_user = sample_user.model_copy(update={"id": "target_user_id", "roles": ["user"]})
+  updated_user = target_user.model_copy(update={"roles": ["admin", "moderator"]})
+  
+  mock_auth_service.get_current_user.return_value = admin_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/users/target_user_id",
+    headers={"Authorization": "Bearer admin.access.token"},
+    json={"roles": ["admin", "moderator"]}
+  )
+  
+  assert response.status_code == 200
+  data = response.json()
+  assert data["roles"] == ["admin", "moderator"]
+  mock_auth_service.update_user.assert_called_once()
+
+
+def test_admin_can_update_user_is_active(client, mock_auth_service, sample_user):
+  """
+  Test admin can update user active status.
+
+  Verifies that an admin can activate or deactivate a user account,
+  which is forbidden for regular users on the /auth/me endpoint.
+  """
+  admin_user = sample_user.model_copy(update={"roles": ["admin"]})
+  target_user = sample_user.model_copy(update={"id": "target_user_id", "is_active": True})
+  updated_user = target_user.model_copy(update={"is_active": False})
+  
+  mock_auth_service.get_current_user.return_value = admin_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/users/target_user_id",
+    headers={"Authorization": "Bearer admin.access.token"},
+    json={"is_active": False}
+  )
+  
+  assert response.status_code == 200
+  # Note: is_active is not in UserResponse, so we just verify the call was made
+  mock_auth_service.update_user.assert_called_once()
+  call_args = mock_auth_service.update_user.call_args
+  assert call_args[1]["updates"].is_active is False
+
+
+def test_admin_can_update_user_is_verified(client, mock_auth_service, sample_user):
+  """
+  Test admin can update user verification status.
+
+  Verifies that an admin can change a user's email verification status,
+  which is forbidden for regular users on the /auth/me endpoint.
+  """
+  admin_user = sample_user.model_copy(update={"roles": ["admin"]})
+  target_user = sample_user.model_copy(update={"id": "target_user_id", "is_verified": False})
+  updated_user = target_user.model_copy(update={"is_verified": True})
+  
+  mock_auth_service.get_current_user.return_value = admin_user
+  mock_auth_service.update_user.return_value = updated_user
+  
+  response = client.patch(
+    "/auth/users/target_user_id",
+    headers={"Authorization": "Bearer admin.access.token"},
+    json={"is_verified": True}
+  )
+  
+  assert response.status_code == 200
+  # Note: is_verified is not in UserResponse, so we just verify the call was made
+  mock_auth_service.update_user.assert_called_once()
+  call_args = mock_auth_service.update_user.call_args
+  assert call_args[1]["updates"].is_verified is True
+
+
+def test_non_admin_cannot_update_other_users(client, mock_auth_service, sample_user):
+  """
+  Test non-admin cannot update other users.
+
+  Verifies that a regular user (without admin role) cannot access
+  the PATCH /auth/users/{user_id} endpoint and receives 403 Forbidden.
+  """
+  regular_user = sample_user.model_copy(update={"roles": ["user"]})
+  mock_auth_service.get_current_user.return_value = regular_user
+  
+  response = client.patch(
+    "/auth/users/other_user_id",
+    headers={"Authorization": "Bearer user.access.token"},
+    json={"username": "shouldfail"}
+  )
+  
+  assert response.status_code == 403
+  assert "admin" in response.json()["detail"].lower()
+
+
+def test_admin_cannot_update_non_existent_user(client, mock_auth_service, sample_user):
+  """
+  Test admin cannot update non-existent user.
+
+  Verifies that attempting to update a non-existent user returns
+  404 Not Found status.
+  """
+  admin_user = sample_user.model_copy(update={"roles": ["admin"]})
+  mock_auth_service.get_current_user.return_value = admin_user
+  mock_auth_service.update_user.side_effect = UserNotFoundError(
+    "User not found"
+  )
+  
+  response = client.patch(
+    "/auth/users/non_existent_id",
+    headers={"Authorization": "Bearer admin.access.token"},
+    json={"username": "shouldfail"}
+  )
+  
+  assert response.status_code == 404
+  assert "not found" in response.json()["detail"].lower()
diff --git a/tests/core/test_auth_service.py b/tests/core/test_auth_service.py
index bb6c63a..1d0c906 100644
--- a/tests/core/test_auth_service.py
+++ b/tests/core/test_auth_service.py
@@ -343,6 +343,297 @@ class TestAuthServiceTokenManagement(object):
       with pytest.raises(ExpiredTokenError):
         auth_service.get_current_user("expired_access_jwt")
 
+
+class TestAuthServiceUserUpdate(object):
+  """Tests for user update operations."""
+  
+  @pytest.fixture(autouse=True)
+  def setup_user(self, auth_service: AuthService, test_user_data_create: UserCreate):
+    """Sets up a registered user for update tests."""
+    
+    pm = auth_service.password_manager
+    original_hash = pm.hash_password.return_value
+    
+    # Temporarily set hash for setup
+    pm.hash_password.return_value = "HASHED_PASS"
+    user = auth_service.register(test_user_data_create)
+    self.user = user
+    self.original_email = user.email
+    self.original_username = user.username
+    
+    # Restore hash mock
+    pm.hash_password.return_value = original_hash
+  
+  def test_i_can_update_user_email(self, auth_service: AuthService):
+    """Success: Email can be updated and is_verified is automatically set to False."""
+    
+    from myauth.models.user import UserUpdate
+    
+    new_email = "updated.email@example.com"
+    updates = UserUpdate(email=new_email)
+    
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.email == new_email
+    assert updated_user.is_verified is False
+  
+  def test_i_can_update_user_username(self, auth_service: AuthService):
+    """Success: Username can be updated."""
+    
+    from myauth.models.user import UserUpdate
+    
+    new_username = "UpdatedUsername"
+    updates = UserUpdate(username=new_username)
+    
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.username == new_username
+  
+  def test_i_can_update_user_password(self, auth_service: AuthService):
+    """Success: Password can be updated and is properly hashed."""
+    
+    from myauth.models.user import UserUpdate
+    
+    pm = auth_service.password_manager
+    new_password = "NewSecurePass123!"
+    
+    with patch.object(pm, 'hash_password', return_value="NEW_HASHED_PASSWORD") as mock_hash:
+      updates = UserUpdate(password=new_password)
+      updated_user = auth_service.update_user(self.user.id, updates)
+      
+      mock_hash.assert_called_once_with(new_password)
+      assert updated_user.hashed_password == "NEW_HASHED_PASSWORD"
+  
+  def test_i_can_update_user_password_and_all_refresh_tokens_are_revoked(
+      self,
+      auth_service: AuthService
+  ):
+    """Success: Updating password revokes all refresh tokens when no current token provided."""
+    
+    from myauth.models.user import UserUpdate
+    
+    # Setup: Create some refresh tokens for the user
+    from myauth.models.token import TokenData
+    from datetime import datetime, timedelta
+    
+    token1 = TokenData(
+      token="refresh_token_1",
+      token_type="refresh",
+      user_id=self.user.id,
+      expires_at=datetime.now() + timedelta(days=1),
+      created_at=datetime.now(),
+      is_revoked=False
+    )
+    token2 = TokenData(
+      token="refresh_token_2",
+      token_type="refresh",
+      user_id=self.user.id,
+      expires_at=datetime.now() + timedelta(days=1),
+      created_at=datetime.now(),
+      is_revoked=False
+    )
+    auth_service.token_repository.save_token(token1)
+    auth_service.token_repository.save_token(token2)
+    
+    # Execute: Update password without providing current token
+    updates = UserUpdate(password="NewPassword123!")
+    auth_service.update_user(self.user.id, updates)
+    
+    # Verify: Both tokens are revoked
+    token1_after = auth_service.token_repository.get_token("refresh_token_1", "refresh")
+    token2_after = auth_service.token_repository.get_token("refresh_token_2", "refresh")
+    
+    assert token1_after.is_revoked is True
+    assert token2_after.is_revoked is True
+  
+  def test_i_can_update_user_password_and_preserve_current_session(
+      self,
+      auth_service: AuthService
+  ):
+    """Success: Updating password preserves the current refresh token when provided."""
+    
+    from myauth.models.user import UserUpdate
+    from myauth.models.token import TokenData
+    from datetime import datetime, timedelta
+    
+    # Setup: Create some refresh tokens
+    current_token = TokenData(
+      token="current_refresh_token",
+      token_type="refresh",
+      user_id=self.user.id,
+      expires_at=datetime.now() + timedelta(days=1),
+      created_at=datetime.now(),
+      is_revoked=False
+    )
+    other_token = TokenData(
+      token="other_refresh_token",
+      token_type="refresh",
+      user_id=self.user.id,
+      expires_at=datetime.now() + timedelta(days=1),
+      created_at=datetime.now(),
+      is_revoked=False
+    )
+    auth_service.token_repository.save_token(current_token)
+    auth_service.token_repository.save_token(other_token)
+    
+    # Execute: Update password while providing current token
+    updates = UserUpdate(password="NewPassword123!")
+    auth_service.update_user(self.user.id, updates, refresh_token="current_refresh_token")
+    
+    # Verify: Current token is preserved, other is revoked
+    current_after = auth_service.token_repository.get_token("current_refresh_token", "refresh")
+    other_after = auth_service.token_repository.get_token("other_refresh_token", "refresh")
+    
+    assert current_after.is_revoked is False
+    assert other_after.is_revoked is True
+  
+  def test_i_can_update_multiple_fields_at_once(self, auth_service: AuthService):
+    """Success: Multiple fields can be updated simultaneously."""
+    
+    from myauth.models.user import UserUpdate
+    
+    updates = UserUpdate(
+      username="MultiUpdateUser",
+      roles=["admin", "member"],
+      user_settings={"theme": "light", "language": "en"}
+    )
+    
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.username == "MultiUpdateUser"
+    assert updated_user.roles == ["admin", "member"]
+    assert updated_user.user_settings == {"theme": "light", "language": "en"}
+  
+  def test_i_can_update_user_roles(self, auth_service: AuthService):
+    """Success: User roles can be updated."""
+    
+    from myauth.models.user import UserUpdate
+    
+    new_roles = ["admin", "moderator"]
+    updates = UserUpdate(roles=new_roles)
+    
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.roles == new_roles
+  
+  def test_i_can_update_user_settings(self, auth_service: AuthService):
+    """Success: User settings can be updated."""
+    
+    from myauth.models.user import UserUpdate
+    
+    new_settings = {"theme": "light", "notifications": True, "language": "fr"}
+    updates = UserUpdate(user_settings=new_settings)
+    
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.user_settings == new_settings
+  
+  def test_i_can_update_is_active_status(self, auth_service: AuthService):
+    """Success: User active status can be updated."""
+    
+    from myauth.models.user import UserUpdate
+    
+    # Deactivate user
+    updates = UserUpdate(is_active=False)
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.is_active is False
+    
+    # Reactivate user
+    updates = UserUpdate(is_active=True)
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    assert updated_user.is_active is True
+  
+  def test_i_cannot_update_user_with_invalid_user_id(self, auth_service: AuthService):
+    """Failure: Updating a non-existent user raises UserNotFoundError."""
+    
+    from myauth.models.user import UserUpdate
+    from myauth.exceptions import UserNotFoundError
+    
+    updates = UserUpdate(username="ShouldFail")
+    
+    with pytest.raises(UserNotFoundError):
+      auth_service.update_user("non_existent_id", updates)
+  
+  def test_i_cannot_update_email_to_existing_email(self, auth_service: AuthService):
+    """Failure: Updating email to an already registered email raises UserAlreadyExistsError."""
+    
+    from myauth.models.user import UserCreate, UserUpdate
+    
+    # Setup: Create another user with a different email
+    other_user_data = UserCreate(
+      email="other.user@example.com",
+      username="OtherUser",
+      password="OtherPass123!",
+      roles=["member"]
+    )
+    auth_service.register(other_user_data)
+    
+    # Execute: Try to update original user's email to the other user's email
+    updates = UserUpdate(email="other.user@example.com")
+    
+    with pytest.raises(UserAlreadyExistsError):
+      auth_service.update_user(self.user.id, updates)
+  
+  def test_i_cannot_update_email_to_same_email_without_triggering_verification_reset(
+      self,
+      auth_service: AuthService
+  ):
+    """Success: Updating email to the same email does not reset is_verified."""
+    
+    from myauth.models.user import UserUpdate
+    
+    # Setup: Ensure user is verified
+    verify_updates = UserUpdate(is_verified=True)
+    auth_service.update_user(self.user.id, verify_updates)
+    
+    # Execute: Update with the same email
+    updates = UserUpdate(email=self.original_email)
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    # Verify: is_verified should remain True
+    assert updated_user.is_verified is True
+    assert updated_user.email == self.original_email
+  
+  def test_i_can_update_with_empty_updates(self, auth_service: AuthService):
+    """Success: Updating with empty UserUpdate does not cause errors."""
+    
+    from myauth.models.user import UserUpdate
+    
+    updates = UserUpdate()
+    updated_user = auth_service.update_user(self.user.id, updates)
+    
+    # Verify: User is returned and fields are unchanged
+    assert updated_user.id == self.user.id
+    assert updated_user.email == self.original_email
+    assert updated_user.username == self.original_username
+  
+  def test_email_verification_reset_only_when_email_actually_changes(
+      self,
+      auth_service: AuthService
+  ):
+    """Success: is_verified is reset to False only when email actually changes."""
+    
+    from myauth.models.user import UserUpdate
+    
+    # Setup: Set user as verified
+    verify_updates = UserUpdate(is_verified=True)
+    auth_service.update_user(self.user.id, verify_updates)
+    verified_user = auth_service.user_repository.get_user_by_id(self.user.id)
+    assert verified_user.is_verified is True
+    
+    # Test 1: Update with same email - verification should remain
+    same_email_updates = UserUpdate(email=self.original_email, username="SameEmailTest")
+    updated_user = auth_service.update_user(self.user.id, same_email_updates)
+    assert updated_user.is_verified is True
+    
+    # Test 2: Update with different email - verification should reset
+    different_email_updates = UserUpdate(email="completely.new@example.com")
+    updated_user = auth_service.update_user(self.user.id, different_email_updates)
+    assert updated_user.is_verified is False
+    assert updated_user.email == "completely.new@example.com"
+
 # class TestAuthServiceResetVerification(object):
 #   """Tests for password reset and email verification flows."""
 #