Among people with HIV, alcohol use is associated with increased prevalence of sexual transmission behaviors. We examined associations between alcohol use in the prior year and sexual behaviors approximately six months later among 1857 women, 6752 men who have sex with men (MSM) and 2685 men who have sex with women (MSW). Any alcohol use was associated with increased risk of unsafe vaginal sex among women; anal sex and =>2 anal sex partners among MSM; and anal sex, =>2 anal or vaginal sex partners, and unsafe vaginal sex among MSW. In particular, among women >7 alcoholic drinks/week and among MSW =>5 alcoholic drinks/drinking day increased the likelihood of certain subsequent sexual behaviors. For all groups, especially women, the risk of sex under the influence of drugs/alcohol markedly increased with increases in quantity and frequency of alcohol consumption. These different patterns of drinking and sexual behaviors indicate the importance of tailored counseling messages to women, MSM and MSW.