This chapter addressed the issues of managing more scalable domain structures and how to create new domains. Windows 2000 introduced two new domain models: mixed mode and native mode. The chapter also looked at the new trust relationship with Active Directory, which is composed of two-way transitive trusts to other domain controllers, while still having the option of setting exclusive one-way trusts. Lastly, it discussed DNS in Windows 2000 and other third-party versions. DNS will be a critical, and controversial, issue for many enterprises looking to implement Active Directory. Chapter 4, "Managing Users, Groups, and Computers," looks into managing users, computers, and DHCP.