In our series “Why Public Health?” we ask Harvard T.H. Chan School of Public Health students and alumni to talk about what drew them to the field. Kimberly Chang, MPH ’15, worked with refugee communities at a health center in Oakland, California, some of them teenage girls involved in sexual trafficking. The experience led her to Harvard Chan to study health policy so that she gains the skills, networks, and leadership ability to move beyond just treating individual patients’ symptoms toward improving their circumstances overall. (2:49)