Designed to reach a wide audience of scholars and policymakers, the Brookings-Wharton Papers on Urban Affairs is an annual series that serves as a forum for cutting-edge, accessible research on urban policy. Tentative contents include:Growth of Medium-Size Cities in China Vernon Henderson (Brown University) The Effects on Driving Patterns, Commuting Times, and Air Quality of New Public Projects to Expand Urban Rail Transit Matthew Kahn (Tufts University) and Nathaniel Baum-Snow (University of Chicago) State Fiscal Constraints and Higher Education Spending Peter Orszag (Brookings) and Thomas Kane (UCLA) Looking Back to Look Forward: What Can We Learn from Philadelphia's 350 Year History? Joseph Gyourko (University of Pennsylvania) The Effect of California's Proposition 13 on Mobility Nada Wasi and Michelle White (University of California, San Diego) Metropolitan Migration in the U.S.: The Impact of Immigrant Minorities, Blacks, and Seniors William Frey (University of Michigan) and Kao-Lee Liaw (McMaster University)