Windows 2000 Domain Types

I work for a medium sized university whose primary network OS is Windows NT. The university will not switch over to Windows 2000 Server until NEXT summer. My department, however, would like to implement a Windows 2000 Server and Exchange 2000. Sincethis will require that I setup Active Directory, here is my question.

How can I setup my domain (Active Directory) in such a way that when the university finally sets up the forest domain that I can add my domain as a tree?