If you are deploying Microsoft Exchange 2000 Enterprise Server, Active Directory is probably the most important underlying Windows service to understand. Exchange 2000 Server uses Active Directory to browse objects, for security, and for name resolution. It additionally uses Active Directory for Group Policy, the address book, user authentication, location of mailbox stores, and other user information. Active Directory also provides a centralized administration point from which you can provision security policies for Exchange. Because of this centralized design, you can delegate administration separately for each company that you host.
Exchange 2000 Server also stores Global Address Lists, Access Control Lists, Offline Address Lists, Recipient Policies, and Exchange service configuration that maps to Active Directory users and groups in the directory.
For more information about delegating administrative control, see Active Directory and Delegated Administration Console. For more information about deploying Exchange 2000 Server and Active Directory, see Additional resources.