The Unified Contact Store is a centralized storage mechanism for contacts (3) for instant messaging clients. It provides two folders: ImContactList and QuickContacts. The ImContactList folder contains groups, which in turn contain contacts (3). In a typical contact list, a user-created distribution list represents the groups in the contact list. The contacts are stored in the QuickContacts folder. These contacts contain the information displayed in the contact list; for example, display name, instant messaging address, phone number, and so on.
The Unified Contact Store Web Service Protocol simplifies integration with the Unified Contact Store. This protocol provides operations for adding and removing instant messaging groups by adding and removing user-created distribution lists in the ImContactList folder. It also provides operations for adding, removing, and changing the group of a contact (3) in the instant messaging groups by adding or removing a contact in the QuickContact folder, and then modifying the membership in the user-created distribution list in the ImContactList folder. This enables instant messaging clients to store, access, and make changes to instant messaging contact lists without requiring additional calls and business logic.