Alcohol and other drug (AOD) use during sexual encounters, sexual partner's age, perceived HIV risk and perceived condom effectiveness were studied among 388 sexually active African American youth. Cluster analysis of condom use, number of partners, and frequency of sexual intercourse identified four groups: low risk, monogamy strategy, condom strategy, and high risk. Low-risk youth used condoms consistently and had few partners. High-risk youth used condoms inconsistently with many partners. Monogamy strategy youth used condoms inconsistently but had few partners. Condom strategy youth used condoms consistently with a moderate number of partners. The high-risk group included more males and the monogamy group included more females. High-risk males reported more AOD use during sexual activity than all females, and low-risk or condom strategy males. Females had older partners, rated condoms as less effective and perceived lower HIV/AIDS risk than males. Results suggest differential HIV risk mechanisms by gender. Implications for gender-specific HIV prevention are discussed.