This report documents the MANHATTAN 2001 Political-Military Game, conducted by the Center for Army Analysis (CAA) for Headquarters, Department of the Army (HQDA), Office of the Deputy Chief of Staff for Operations and Plans (ODCSOPS), now the Deputy Chief of Staff, G3, Operations, Readiness, and Mobilization Directorate (DAMO-OD). The purpose of this report is to provide an overview of MANHATTAN 2001, to include a summary of insights gained from the game. The intent of MANHATTAN 2001 was to obtain an executive-level view of Army infrastructure assurance as it supports the Department of Defense (DoD) Critical Infrastructure Protection program, to further refine Army infrastructure assurance as a mission area for Army Homeland Security, and to examine the Army’s infrastructure assurance strategic challenges.