Nothing has stamped Haiti more than the AIDS epidemic. In 1986, a major AIDS prevention campaign was launched, consisting mostly of radio and television messages, billboards, face-to-face contact, and condom promotion. The evaluation of the prevention efforts clearly indicates that they are insufficient to curb the epidemic: (1) although knowledge about AIDS has increased, it is not associated with appreciable behavioral changes; (2) condom sale has increased in urban areas but not in rural areas, where 70% of the population live; (3) HIV seroprevalence surveys in comparable populations studied in 1986 reveal an increase in both urban and rural areas; (4) HIV seroconversion among discordant couples remains high despite counseling and free availability of condoms (7.34/100 person-years of observation). Although preventive efforts should continue, they are clearly insufficient to curb the epidemic. Vaccine intervention offers the only alternative, and heterosexually active, discordant couples are an ideal target for vaccine efficacy trials.