The local supply of physicians in any community, especially smaller and rural communities, depends on a flow of physicians into those communities from the places where they train or from more populous places that may have more than enough physicians to meet population needs. The factors that influence whether a physician will move from one place to another depends on their personal characteristics, the places from and to which they move, and the programs that support or inhibit those moves. In this webinar, Tom Ricketts describes his work on physician diffusion, and helps explain its effects and policy implications on underserved areas.