My research interests are in the areas of applied health and behavioral economics, with a special focus on the economic aspects of HIV treatment and prevention, and health systems in low- and middle-income countries. A large portion of my research in health economics has concerned the impact of health reform and insurance expansion decisions. My research on health systems reform has led to publications evaluating the impact of social health insurance programs (such as Seguro Popular in Mexico, the National Hospital Insurance Fund in Kenya, and Medicaid in the U.S.) on various economic and health outcomes. I have also published research on the effects of conditional and unconditional cash transfers (and economic incentives) for health behavior change, including incentives to exercise as well as incentives to improve HIV prevention and treatment outcomes. Other papers have concerned economic efficiency research (including cost effectiveness, cost benefit and cost utility studies).