Naturally, the communication link between the onsite project manager and the offsite team is very critical. So you will want a team that has worked together before. Everyone must be on the same page in terms of methodology.
Furthermore, the project managers and business analysts on both sides should work very closely throughout the project. Meaning, they should have constant contact to ensure that all questions are answered quickly, and any issues are resolved immediately.
Depending on the complexity and size of the project, there will be some variation to this process. Generally speaking though, the model outlined here should be the guideline foundation for any project.