This twenty-year study analyzes changes in sexual behavior among students at Okanagan University College in British Columbia, Canada. Surveys conducted in 1980, 1990, and 2000 reveal a steady increase in safer sexual practices. Most students now question potential partners about their past, use condoms with a new sexual partner, and maintain fairly long-term monogamous relationships. Three sexual subcultures continue to coexist in fairly stable proportions: celibacy (about 30%), monogamy (about 60%), and free experimentation (about 10%). Each subculture has created its own response to the danger of HIV/AIDS: celibates exaggerate the danger they face, monogamists rely on love and fidelity for protection, and free experimenters have increased their use of condoms. While romantic feelings lead many monogamous couples to abandon condoms without objective HIV/AIDS knowledge, free experimenters still face the highest risk. Although they now use condoms more than half the time, their lifestyle, which involves multiple partners, risky sexual acts, and frequent drug and/or alcohol use, clearly remains dangerous. The persistence of distinct subcultures has implications for health education programs, which would be most effective if based on key values held by specific target groups.