This study evaluated the short-term effectiveness of a mixed-gender sexual assault prevention program developed for college students. Program participants (n = 177) were compared to non-program participants (n = 132) prior to the program and during a 2-week follow-up period on measures of rape myths, victim empathy, perceived negative consequences and estimated likelihood of committing rape, sexual communication, sexual assault awareness, and risky dating behavior. The prevention program was effective at increasing men's victim empathy and decreasing their adherence to rape myths but ineffective at changing women's assault-related knowledge, participation in risky dating behaviors, and sexual communication strategies. Limitations of the study and directions for future research in sexual assault prevention are addressed. Editors' Strategic Implications: This study provides an important example of the limitations of a single session prevention programming approach (even if it is well designed and executed) in addressing a systemic and pervasive problem like sexual assault on college campuses.