Although in the past the field of youth development has been subsumed within or occluded by other traditional development sectors such as education, a re-emerging emphasis on security in US government foreign assistance has tended to foreground youth as a frame of reference for international development programming and public diplomacy. While youth as security threat is by itself a reductive formulation, there are opportunities to grasp more deeply the power of young cohorts to affect social change in multidimensional ways. This article examines how youth issues have been framed within broader policy and program priorities of the United States Agency for International Development (USAID), especially in post-conflict/fragile states, in an effort to illuminate some key dilemmas and knowledge gaps. (Contains 2 notes.)