Youth enrolled in dropout prevention and alternative school programs engage in high-risk behaviors in greater numbers than those in traditional school settings. However, data on alcohol and drug use influences and risky sexual behavior are often not collected or reported among these youth because of small enrollments and rapid turnover. This study surveyed alcohol and drug use and sexual behaviors among 212 youths in dropout prevention. Use of alcohol and drugs and age of sexual initiation were significantly associated with a high-risk profile score for HIV/AIDS. Of sexually active youth, 28 percent used alcohol or drugs prior to having sexual intercourse and more than half had not used condoms during their last sexual experience. Males were more likely than females to use alcohol and drugs before having sex, and were more likely to have had sex with two or more partners. Findings suggest that, among youth in dropout prevention, the association of alcohol and drug use with HIV/AIDS risk is significant and that prevention programs should target alcohol and drug use as important influences on risky sexual behavior. Tables, references