Microsoft Windows 2000 - Update: The Active Directory 
Overview/Description
To describe how to install, configure, and administer the Active Directory, and how to create key Active Directory objects such as users and groups
Target Audience
Existing MCSEs and Windows NT 4.0 administrators who have early adoption experience of Windows 2000 and who wish to upgrade their certification and support skills to Windows 2000
Prerequisites
Windows NT 4.0 MCSE qualification or good working knowledge of Windows NT 3.51 or Windows NT 4.0 from administrative, support, and architectural perspectives; early adoption experience of Windows 2000 Professional and Server
Microsoft Windows 2000 - Update: The Active Directory