You might need to create users, resources, or distribution lists that are not available to all GroupWise users. You can accomplish this by restricting the set of users that can see such objects in the Address Book. You can make such objects visible only to the members of a domain, only to the members of a post office, or to no one at all. An object does not need to be visible to be addressable. For instructions, see Section 6.2, Controlling Object Visibility.