Brian Gill (Ph.D., J.D.) is a Senior Fellow at Mathematica Policy Research in Cambridge, MA. His work addresses a variety of topics in K-12 education policy, including charter schools, measurements of teacher and school effectiveness, and the implementation and impacts of the federal No Child Left Behind Act (NCLB). Gill is one of the nation’s leading experts on the effects of charter schools. He served as principal investigator on the first nationwide evaluation of the effects of the KIPP schools, and co-directed the first study of the effects of charter high schools on rates of graduation and college entry. As a principal investigator with the Mid-Atlantic Regional Education Laboratory, Gill is playing a leading role in the development of multiple measures of teacher and principal performance in several states and districts. He is also serving as principal investigator for the U.S. Department of Education’s implementation study of Title I of the Elementary and Secondary Education Act.