Wikka supports fine-grained ACL management on a per-page basis. Distinct ACL settings control who can read, write or post comments to a page. A simple and flexible syntax allows page owners (and administrators) to edit ACL settings for single pages so as to make them read-only, writable by a restricted number of users, writable by registered users only, private, restricted to administrators only etc. System-wide ACL that automatically apply to any newly created page can be specified by the wiki administrator. User group support for ACL is currently under development.