Grant Miller's current research focuses broadly on behavioral obstacles to health improvement in developing countries. One line of studies investigates household decision-making underlying puzzlingly low adoption rates of highly efficacious health technologies (like point-of-use drinking water disinfectants and improved cookstoves) in many poor countries. Another vein of research investigates misaligned macro- and micro-level incentives governing the supply of health technologies and services. He has conducted these and other research projects at institutions including the National Bureau of Economic Research, the Urban Institute, and the University of California-San Francisco's Institute for Health Policy Studies.

Miller received a BA in psychology from Yale College, a master's degree in public policy from the Kennedy School of Government at Harvard University, and a PhD in health policy/economics also from Harvard.