This report examines how the U.S. government -- primarily the Departments of Defense (DOD), State, Treasury, and Justice (DOJ), and the U.S. Agency for International Development (USAID) -- understood the risks of corruption in Afghanistan, how the U.S. response to corruption evolved, and the effectiveness of that response. The report identifies lessons to inform U.S. policies and actions at the onset of and throughout a contingency operation and makes recommendations for both legislative and executive branch action. This analysis reveals that corruption substantially undermined the U.S. mission in Afghanistan from the very beginning of Operation Enduring Freedom. It concludes that failure to effectively address the problem means that U.S. reconstruction programs, at best, will continue to be subverted by systemic corruption and, at worst, will fail. Figures and tables.. This is a print on demand report.