After fifteen years of war in Afghanistan and Iraq, many now see “small-footprint” security force assistance (SFA)–training, advising, and equipping allied militaries–as an alternative to large U.S. ground-force commitments to stabilize weak states. SFA, however, confronts challenges of interest misalignment between the United States and its typical partners. The resulting agency losses often limit SFA's real ability to improve partners' military effectiveness. For SFA, small footprints usually mean small payoffs.