Using the User List Properties Dialog To Manage User List Members and Owners, or User List Membership in Other User Lists

Select the User Lists node.
Right-click a user list and select Properties. The User List Properties dialog opens.
To manage user list members, select the Members tab.

To add members, click Add, then select one or more users, groups, and/or user lists in the Select Security List dialog and click OK. The selected members are added to the Members tab

or
To remove members, select one or more users, groups, and/or user lists in the Members tab and click Remove.

Note: If the user list you are adding members to is an access list, then your members can be users, groups, or other access lists. If the user list is a mailing list, then your members can be users, groups, or other mailing lists (Global Address Books).
To manage user list owners, select the Owners tab.

To add owners to this user list, click Add, then select one or more users and/or user lists in the Select Users or User Lists dialog and click OK. These users and/or user lists are added to the Owners tab.

or
To remove owners from this user list, select one or more users and/or user lists on the Owners tab and click Remove.

Note: Make sure that each user you want to make an owner of this user list has the user setting, Administrative - Enable group and user list ownership, turned on. Whenever a user list is an owner of another user list, only the members of the (owner) user list who have the above user setting turned on will actually be owners of the user list.
To manage this user list's membership in other user lists, select the Member Of tab.

To add this user list to another user list, click Add, then select one or more user lists in the Select User Lists dialog and click OK. These user lists are added to the Member Of tab.

or
To remove this user list from another user list, select one or more user lists on the Member Of tab and click Remove.
When finished making changes, click OK on the User List Properties dialog.