Discusses how the rapid diffusion of advanced technology throughout the world has the potential to challenge the U.S. technological advantage in defense capabilities. In this paper, the authors urge the United States to refrain from assuming that its current advantages will continue in the absence of sustained attention to both policy and investment choices and urge the nation to redouble its focus on sustaining technological dominance. The authors make recommendations to ensure that the United States maintains its technological dominance for years to come, including congressional legislation requiring DOD to issue annual reports on defense research and development across the enterprise, the creation of a standing DOD next-generation technology task force, and initiation of a multiyear series of war games on how technological advances may alter military competition around the world.