William Clark is professor emeritus of geography at the University of California, Los Angeles (UCLA). He is truly an outstanding scholar of geography, earning the American Association of Geographers (AAG) 2018 Lifetime Achievement Award. Notably, Professor Clark is a member of the National Academy of Sciences, the American Academy of Arts and Sciences, and was a 1994 Guggenheim Fellow. He also received a College of LAS Alumni Achievement Award in 2006.

Clark's research contributions are extensive, but his main interest is in urban geography, particularly housing choices, residential mobility, and residential sorting; patterns of segregation and the social organization of cities, and migration and labor market outcomes.