You can create contact groups to organize the people in your Office Communicator Contact List. After you create a group, you can right-click the group name in your Communicator Contact List, and then send an instant message, for example, to all members of the group.
Create a contact group
In the Office Communicator main window, right-click an existing group name, and then click Create New Group.
In the New Group text box, type a name for the group, and then press ENTER.
You can drag existing contacts from the Contact List into the group or use the Communicator Search feature to find contacts and add them to the group.