The authors use longitudinal data from one large school district to investigate the distribution of principals across schools. They find that schools serving many low-income, non-White, and low-achieving students have principals who have less experience and less education and who attended less selective colleges. This distribution of principals is partially driven by the initial match of first-time principals to schools, and it is exacerbated by systematic attrition and transfer away from these schools. The authors supplement these data with surveys of principals and find that their stated preferences for school characteristics mirror observed distribution and transfer patterns: Principals prefer to work in easier-to-serve schools with favorable working conditions, which tend to be schools with fewer poor, minority, and low-achieving students. (Contains 13 notes, 9 tables, and 1 figure.)