Washington, D.C., is the capital of the United States and is a major center for public health and health policy expertise. Yet the District of Columbia has an HIV prevalence rate among adults of 3 percent, on par with some sub-Saharan African countries. To date, the local public health response has not controlled the epidemic. The ways in which that response has been galvanized in recent years--through collaboration among the capital's public health agencies, community and faith organizations, and research institutions--may be instructive to other jurisdictions combating HIV/AIDS.