When you enter the administrator permissions section (Usergroups > Administrator Permissions), you will see a screen like this:
Every administrator will be listed on this page. To see what they have done in the control panel, click [View Control Panel Log]; to edit their control panel permissions, click [Edit Permissions].
The [Edit Permissions] link will take you to this page:
Each of the settings in this list refers to a specific area in the control panel. For example, if you set Can Administer Settings to no, this user will not be able to see the vBulletin Options group in the left frame of the control panel. Each setting refers to one or more groups of options in the left frame.
Additionally, you may specify the control panel style this user will use, unless he or she changes it while logging into the control panel.
To access the administrator permissions section, you must be a Super Administrator; if you are not, you will receive an error message when trying to access this area. To become a super administrator, you must edit your includes/config.php file and add your user ID to the $superadministrators line. See Editing the vBulletin Configuration File for more information.