This chapter examines professional cross-training as one strategy to meet the multiple needs of people living with HIV/AIDS. Cross-training is a mechanism to coordinate care at the client level, where providers (and sometimes clients) receive training in service systems outside of their primary service involvement, as well as training in cultural competence. Another strategy for client-level integration is the use of multidisciplinary treatment teams, where providers with different areas of expertise meet and plan for coordinated treatment for their clients. Both cross-training and multidisciplinary treatment teams seek collaborative models of care that revolve around the specifi c needs of a given client. This chapter focuses on cross-training, and is based on the experience of a group of providers who worked together to develop a curriculum for cross-training (referred to as the Common Ground), and who implemented this cross-training over the course of several years and subsequently trained new faculty to conduct cross-training. This chapter is arguably the most applied in the book, in that it builds on years of collaborative experience doing cross-trainings by providers and educators to provide a “how-to” model for cross-training. Consequently, this chapter will be useful to those who are actually seeking to implement cross-training, or for those who want to increase the effectiveness of multidisciplinary treatment teams.