USAID’s nutrition research has positioned the Agency to not only lead in shaping evidence-based policies, but to be at the forefront of innovative technology creation and scalable program development. This research has deepened the global understanding of the causes and consequences of malnutrition and provided proven, cost-efective solutions. USAID applies a systematic and coordinated “research-to-policy-to-programs” approach, which has translated research into large-scale applications that have significantly improved the nutritional status and survival of children. Advances in measuring individual and population-level malnutrition indicators provide indispensable data for decision-making, for revealing malnutrition’s magnitude and for tracking the world’s progress toward better nutrition for all. This chapter highlights some of USAID’s major nutrition research and measurement contributions.