With increasing competition for resources, health departments are faced with the question of whether to target female prostitutes as a high priority component of AIDS prevention strategy. Prostitutes are considered to be a reservoir for transmission of certain sexually transmitted diseases (STDs). However, a variety of studies suggest that human immunodeficiency virus (HIV) infection in prostitutes follows a different pattern than that for STDs: HIV infection in non-drug using prostitutes tends to be low or absent, implying that sexual activity alone does not place them at high risk, while prostitutes who use intravenous drugs are far more likely to be infected with HIV. Emerging data from heterosexual groups similarly suggest a low rate of heterosexual transmission, particularly from women to men. Prostitutes who do not use intravenous drugs probably face their highest risk from steady partners who may be infected with HIV and other STDs and with whom barrier protection is generally not used. Nevertheless, there are good reasons for health departments to place high priority on prevention efforts directed to prostitutes: 1) prostitutes often have other risky behaviors such as drug use; and 2) prostitutes are reachable, being a group which is already in the health care system administered by health departments.