Marc Stein is the Executive Director of the Improvement Colaboratory at Improving Education. Formerly, he was an associate professor in the School of Education at Johns Hopkins University and the research co-director of the Baltimore Education Research Consortium (BERC). He was also a faculty associate with the Hopkins Population Center (HPC) and a faculty affiliate with the Center for Social Organization of Schools (CSOS). His research interests and agenda lie in quantitative and mixed methods analyses of the social contexts surrounding schools and schooling, and the role that these contexts play in the enactment of educational policy. He is especially interested in how educational policy can exacerbate or ameliorate racial-ethnic, socioeconomic and other inequalities. He has conducted experimental, quasi-experimental and mixed-methods research on a range of topics that include the instructional conditions of charter public schools, parent involvement in charter public schools, the effect of choice on student sorting by race and academic achievement and summer programs and summer learning loss.