User statuses represent user groups, and each status can have a specific set of privileges. User statuses have a hierarchical structure (a subordinated user status cannot have more privileges than a parent user status). A user can be included in several different groups, and the user status set can be different for different projects. 

The list of effective statuses for a task is determined on the basis of the user's own default statuses, and any assigned statuses. To perform a particular action, the action should be permitted for at least one of the user's effective statuses. You can set users' default statuses when creating user accounts, or, you can use the Current User -> User... -> Edit page to edit an existing user's default status. Use the Current Task -> Access Control Rules... -> Assigned Statuses tab to assign statuses for tasks and use the Current User -> Access Control Rules... -> Assigned Statuses tab to assign statuses for users. 

To configure what tabs users can view, use the Current User -> Statuses... menu item.

• To configure what buttons and menu items users can press, use the Current User -> Statuses... menu item.
• To configure what standard task and user fields users can view and edit, use the Current User -> Statuses... menu item.
• To configure what custom fields users can view and edit, use the Current Task -> Custom Fields... -> Permissions or Current User -> Custom Fields... -> Permissions tab.
• For workflow-based custom fields you can specify user accounts which can view and edit custom field values in the Add Message pulldown. Click the Current Task -> Workflows... menu item, choose custom field and use the Message Type Permissions tab to configure it.
• To configure what tasks users can create, view, modify and delete, use the Current Task -> Categories... -> Permissions tab.
• To configure what messages users can view and add, click the Current Task -> Workflows... menu item, choose message type and use the Permissions tab.