This is the user management screen.  You can view the user tree, add or remove permissions belonging to a user, update their data records and perform all user maintenance from this one screen.  No jumping back and forth from one view to another.  This image shows the view from a 1280x1024 monitor, but the view is fne -- no horizontal scrollbars -- at 1024x768 as well.
This is the permission management screen.  You can add permissions and groups to the system, delete them, replace them globally,create and manage permission profiles, view the audit log and see Who's On.  Again, all from the same screen.  Once again this screen shot is from a 1280x1024 screen but 1024x768 works fine as well.