Collaboration matters in science. Yet, while there is intriguing evidence that the organization of scientific collaboration is changing, and that teams are becoming more important, the analysis has been mostly based on studying the results of collaborations as evidenced by co-authorship of publications or patents at the scientist level. There are a number of unanswered questions about the structure of the fundamental unit of scientific production: the project team. Who works on scientific teams? What is the role of postdoctoral fellows and graduate and undergraduate students? How do scientific networks of collaboration evolve in response to federal funding decisions? And how do different network structures affect scientific productivity, in both creation of knowledge and diffusion of results? Federal science policy, which emphasizes the importance of diversity in science, is hampered by an almost complete lack of knowledge of the composition of teams at the funded project level, much less the outcomes. The members of this panel use cutting edge new data to examine both the structure of scientific teams and the effects on the outcomes for women in