I have a large NT4 domain with about 17 resource domains. I am going to install AD. I understand that if I install it in my current NT4 domain I will run in mixed mode untill I upgrade my 50 (BDCs) and the other 30 stand alone systems to 2000. But if I install AD in a new domain could I have that domain in native mode, if so will users in the new 2000 domain be able to access the old nt4 domain? Also will users in the old domain be able to access the new 2000 domain ?