Thomas E. Mann is the W. Averell Harriman Chair and senior fellow in Governance Studies at The Brookings Institution. He is a former executive director of the American Political Science Association. He lives in Bethesda, Maryland. Norman J. Ornstein is a resident scholar at the American Enterprise Institute and the author of a weekly column for Roll Call, called Congress Inside Out." He lives in Washington, D.C. Both are fellows of the American Academy of Arts and Sciences.