Peter Piot, founding executive director of the Joint United Nations Programme on HIV/AIDS (UNAIDS), recounts his experience as a clinician, scientist, and activist fighting the disease from its earliest manifestation to today. The AIDS pandemic was not only catastrophic to the health of millions worldwide but also fractured international relations, global access to new technologies, and public health policies in nations across the globe. As he struggled to get ahead of the disease, Piot found science does little good when it operates independently of politics and economics, and politics is worthless if it rejects scientific evidence and respect for human rights. Piot describes how the epidemic altered global attitudes toward sexuality, the character of the doctor-patient relationship, the influence of civil society in international relations, and traditional partisan divides. AIDS thrust health into national and international politics where, he argues, it rightly belongs. The global reaction to AIDS over the past decade is the positive result of this partnership, showing what can be achieved when science, politics, and policy converge on the ground. Yet it remains a fragile achievement, and Piot warns against complacency and the consequences of reduced investments. He refuses to accept a world in which high levels of HIV infection are the norm. Instead, he explains how to continue to reduce the incidence of the disease to minute levels through both prevention and treatment, until a vaccine is discovered.