Her primary work focuses on teacher and teaching quality, and the effects of policies aimed at improving both. She is also known for developing instruments for measuring teachers’ mathematical knowledge for teaching (MKT) and the mathematical quality of instruction (MQI) within classrooms. Hill is codirector 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 knowledge use within the public sector and the role that language plays in the implementation of public policy. She has served as section chairs for the American Educational Research Association and Society for Research on Educational Effectiveness conferences, and on the editorial boards of Journal of Research in Mathematics Education and the American Educational Research Journal. She is the coauthor, with David K. Cohen, of Learning policy: When state education reform works (Yale Press, 2001).