This study examined the prevalence of sexual aggression and victimization in a large convenience sample of N = 2,149 first‐year college students from different universities in Germany. Participants were asked about both victimization by, and perpetration of, sexual aggression since the age of 14. Both same‐sex and heterosexual victim–perpetrator constellations were examined. Prevalence rates were established for different victim–perpetrator relationships (partners, acquaintances, strangers) and for incidents involving alcohol consumption by one or both partners. The overall perpetration rate was 13.2%, for men and 7.6% for women. The overall victimization rate was 35.9% for women and 19.4% for men. A disparity between victimization and perpetration reports was found for both men and women. Perpetration and victimization rates were highest among participants who had sexual contacts with both opposite‐sex and same‐sex partners. Sexual aggression and victimization rates were higher between current or former partners and acquaintances than between strangers. Alcohol consumption by one or both partners was involved in almost 75% of all victimization and almost 70% of all perpetration incidents. The findings portray a comprehensive picture of the scale of sexual aggression and victimization in college students with different sexual lifestyles. Aggr. Behav. 39:391–404, 2013. © 2013 Wiley Periodicals, Inc.