JEANNE BROOKS-GUNN is Virginia and Leonard Marx Professor of Child Development at Teachers College, Columbia University. She is also director of the Center for Children and Families and founder of the Adolescent Study Program at Teachers College. GREG J. DUNCAN is professor of education and social policy and a faculty associate in the Institute for Policy Research at Northwestern University. He is also faculty affiliate of the Northwestern University/University of Chicago Joint Center for Poverty Research. J. LAWRENCE ABER is director of the National Center for Children in Poverty at the Columbia School of Public Health, Columbia University.