Since 1996, the Commonwealth Fund has offered a yearlong fellowship to physicians committed to transforming health care delivery systems for vulnerable populations, including people of color and economically disadvantaged groups. As part of our centennial celebration, we interviewed two alumni about how the fellowship shaped their careers: 2000–01 fellow Seiji Hayashi, M.D., M.P.H., director of medicine at the Human Diagnosis Project, and 2010–11 fellow Kamillah Wood, M.D., M.P.H., senior vice president of health and housing at Stewards of Affordable Housing for the Future.