From 1994 to 2007, she was a faculty member of Harvard University, first as an assistant professor, then as Morris Kahn Associate Professor of Economics, and starting in 2001 as the Allie S. Freed Professor of Economics. She was the university's only African-American economics professor with tenure. In 2005, she was appointed to be one of the 24 Harvard College Professors. In 2006, she won the "Phi Beta Kappa" Teaching Prize. She moved to Stanford University in 2007, where she is the Scott and Donya Bommer Professor of Economics. She was named the John and Lydia Pearce Mitchell University Fellow in Undergraduate Education in 2014.