Orally administered preexposure prophylaxis is an innovative and controversial HIV prevention strategy involving the regular use of antiretroviral medications by uninfected individuals. Antiretroviral medications protect against potential HIV infection by reducing susceptibility to the virus. Recent clinical trial results indicate that preexposure prophylaxis can be safe and efficacious for men who have sexual intercourse with men, yet there remain policy considerations surrounding costs, opportunity costs, and ethical issues that must be addressed before broad implementation in the United States.