Differences in male (N = 148) and female (N = 278) college students' use of sexually harassing and coercive behaviors were investigated. Men were twice as likely to be sexually harassing and 3 times more likely to be sexually coercive as women. Among men, sexual harassment was predicted by child sexual abuse, hostility, adversarial heterosexual beliefs, and alcohol expectancy, with the latter mediating the effects of aggression. Sexual coercion was predicted by adult sexual victimization and alcohol expectancy, with alcohol expectancy again mediating the effect of aggression. Among women, sexual harassment was predicted by adult sexual victimization, adversarial heterosexual beliefs, aggression, and alcohol expectancy, with aggression mediating the effect of adversarial heterosexual beliefs and alcohol expectancy, mediating the effect of aggression. Sexual coercion was predicted by a hostile personality, which mediated the effects of both child and adult sexual victimization. These findings suggest both gender similarities and differences in determinants of sexual aggression.