HIV has changed in the presence of recent biomedical technologies. In particular, the development of anti-retroviral therapies (ARVs) for the treatment of HIV was a significant landmark in the history of the disease. Treatment with ARV drug regimens, which began in 1996, has enabled many thousands to live with the human immunodeficiency virus without progressing to AIDS. Yet ARVs have also been fraught with problems of regimen compliance, viral resistance, and iatrogenic disease. Besides intensifying the technological and ethical complexities of medicine, the drugs have also affected conceptions of risk and risk practices, in turn presenting new challenges for prevention.