This study examined the impact of sources of AIDS education on HIV-related behavioural changes, and its implications for HIV prevention and service delivery in Nigeria. We analysed cross-sectional data obtained from a structured face-to-face interview with 1,373 respondents aged 15-50, who have ever had sex in Ibadan, Nigeria. Knowledge of HIV/AIDS, its route of transmission and prevention strategies was high. About 20 % of the respondents were exposed to the AIDS prevention campaigns. A majority reported sexual behavioral changes, which included restriction of sex partners, use of condoms, sexual abstinence and avoidance of casual sex. Thirtynine percent took some steps to reduce risk of infection by avoiding transfusion with unscreened blood and testing for HIV status. Using multiple logistic regressions, the factors affecting the reported changes were identified. The application of health belief model shows that the model cannot wholly explain the changes in behavior. The role of female powerlessness in safer sex decision-making is noted. Despite the limitations of the study, the need for a sustained AIDS prevention campaign is stressed. The implications of the study for AIDS programs and research are highlighted.