The Permissions tab of the Function property sheet has the following components:
Users list Lists the users who have permissions on the function. If you want to add users to the list, click Grant. To remove permissions from a user, select the user and click Revoke. You can select multiple users by holding Shift while you click.
Click the Execute field beside each user to grant or revoke permissions.
Grant Displays the Grant Permissions dialog, which lets you grant permissions for the function to other users or groups.
Revoke Revokes permissions for the function from the user or group and removes them from the Users list.