I.O.U.S.A. is a 2008 documentary that examines the national debt crisis and the consequences for the nation and Americans. The film follows David Walker, former U.S. Comptroller General, as he travels across the country on the "Fiscal Wake-Up Tour" speaking about the nation's unsustainable fiscal practices. While the United States has historically faced difficulties in meeting expenditures with existing revenue, Walker explains that today the country faces a new challenge with an expanding government and military, increased international competition, overextended entitlement programs, and increased debts to foreign countries. I.O.U.S.A features five parts, each discussing specific aspects of the national debt: Fiscal Overview, Budget Reform, Defense and Other Spending Reform, Health Care Reform and Tax Reform. Potential financial scenarios are discussed along with possible solutions to regain the fiscal soundness of the nation. The film includes interviews with taxpayers, government officials and the nation's leading experts including Warren Buffett and Alan Greenspan.