In order to evaluate the frequency of sexual transmission of human immunodeficiency virus (HIV) among promiscuous heterosexuals, we studied the prevalence of HIV infection among a group of predominantly Caucasian call girls and women working for escort services and massage parlors in New York City. In the 78 subjects studied, the mean age was 31.6 years and the mean duration of prostitution was 5.1 years. Study participants each had a median of 200 different sexual partners in the preceding year. Six women had a history of intravenous drug abuse and none had a history of any other recognized risk factor for HIV infection. Ninety percent of the women studied used condoms during intercourse with at least some of their partners. One of the six women with a history of drug abuse and none of the 72 non-drug-abusers were seropositive for HIV. This study indicates that despite their promiscuity, HIV infection is still uncommon in call girls in New York City.