William G. Howell is an associate professor in the Government Department at Harvard University and deputy director of the Program on Education Policy and Governance at Harvard. Paul E. Peterson is the Henry Lee Shattuck Professor of Government at Harvard, the director of PEPG, and a senior fellow at the Hoover Institution. He is author or editor of numerous books, including The Education Gap: Vouchers and Urban Schools, with William G. Howell (Brookings, 2004 and 2006). He is coeditor (with Martin West) of No Child Left Behind? The Practice and Politics of School Accountability (Brookings, 2003).