The development of a safe and effective AIDS vaccine is the primary goal of AIDS vaccine research and, once achieved, will have a remarkable impact on reducing the spread of HIV. But there are other added benefits. Conducting AIDS vaccine research in developing countries also strengthens their health systems by reinforcing their research capacity and contributing to health system functioning more broadly. This fact sheet examines the impact of AIDS vaccine research on health systems strengthening in five key areas: the training and retention of human resources; infrastructure development; institutional development; improved health services; and enhanced HIV services.