Heather C. Hill is an associate professor at the Harvard Graduate School of Education. Her primary work focuses on developing measures of mathematical knowledge for teaching and the mathematical quality of teaching, and using these measures to evaluate public policies and programs intended to improve teachers' understanding of this mathematics. She is co-director of the National Center for Teacher Effectiveness and also principal investigator of a five-year study examining the effects of Marilyn Burns Math Solutions professional development on teaching and learning. Her other interests include the measurement of instruction more broadly, instructional improvement efforts in mathematics, and the role that language plays in the implementation of public policy. She received a doctorate in political science from the University of Michigan in 2000 for work analyzing the implementation of public policies in law enforcement and education. She has served as section chair for AERA division L (politics and policy), and on the editorial board of Journal of Research in Mathematics Education. She is the co-author, with David K. Cohen, of Learning policy: When state education reform works (Yale Press, 2001).