Currently, U.S. armed forces are facing a rapidly shifting environment. Even as the major combat operations in Afghanistan and Iraq that defined the last decade are coming to an end, a wide variety of new and evolving challenges, both abroad and at home, are confronting the nation's military. The U.S. Army National Guard faces a unique set of dynamics, given its role in domestic as well as overseas operations. As the Army National Guard considers its future, it asked the CSIS Homeland Security and Counterterrorism Program to provide an independent analysis of the strategic-level issues facing the Guard, as well as its evolving roles and missions. This report provides policymakers and practitioners with objective insights and recommendations to assist in outlining potential future responsibilities for the Army National Guard.