PIP: In a major change of official responses to prostitution many programs strive to reduce the incidence of infection by the human immunodeficiency virus (HIV) and by sexually transmitted diseases (STDs) among sex workers and clients by encouraging safer sex, albeit still trying to ensure that only HIV-negative people engage in sex work. Legal sanctions have been used to limit the activities of seropositive sex workers under the assumption that sex workers with HIV will transmit the virus because of a high prevalence of unprotected sex practices in some places. Where safer sex is the norm for commercial sex transactions, the concern is that sex workers may neglect safe practices and customers may become infected. The fact is that often the clients demand unprotected sex, even when sex workers prefer to use condoms. The risk of accidental infection when protected sex is practiced may even be lower in commercial transactions in which at least one partner is very experienced in condom use and other safe practices. It is usually assumed that HIV-positive sex workers will not inform clients of their status, however, and clients will not inform sex workers of their serostatus either. Where sex workers practice safe sex, intervention programs should provide education on condom use and ensure the availability of inexpensive condoms. In addition to gynecological, antenatal and STD services, health and social services, including child care and legal support, have to be easily accessible. Religious and cultural impediments to realistic HIV/STD prevention should be studied in order to modify or eliminate them. Sex workers who are seropositive probably behave similarly to other people in a community with regard to exposing others to risk, and they are careful about not infecting others, especially if it is guaranteed that their environment supports them.