[ActiveDir] Domain Migration

[Patton, Jim]

I am currently work for a startup, (not a dot-bomb), that is in the process of becoming independent from our parent company. At this time, all IT-related resources are provided by our parent company. I would prefer to build a brand-new Active Directory infrastructure from the start. However, because of the current economic climate, I’ve had to develop some alternative plans.   Ultimately, the goal is to become fully independent with a completely separate IT infrastructure. I can envision three possible scenarios:   1) Create a new child domain within the existing infrastructure, create a new Exchange server and complete the migration all user accounts and data, transition the remaining IT-resources to the new child domain, (SQL 2000 & Sharepoint) and then eventually migrate the child domain to a new Active Directory Tree / Forest?   2) Create a new Tree and Domain within the existing Forest, migrate all IT-resources and then transition everything to a new Forest.   3) Create a new Active Directory Forest, establish a two-way trust between both Forests, and then begin the migration of IT-resources starting with the Exchange and other user-specific data.   Does anyone have any recommendations, suggestions or advice on the best path to take with the ultimate goal in mind?   Thanks   Jim