Objective: Assess the efficacy of a college dating abuse (DA) prevention workshop. Participants: 85 students from Greek organizations. Methods: Two fraternities and two sororities were randomized to intervention or waitlist control. Participants completed a baseline and 3-month follow-up survey. Data were analyzed using MANOVA. Results: As compared to those in the control group, students assigned to the DA workshop felt more prepared to act as bystanders at follow-up and were more convinced that DA was a problem on campus. Those who saw the workshop also recognized more opportunities when they could intervene as bystanders with friends and strangers at follow-up than did controls. Conclusions: The DA workshop appears to have influenced students in the desired way, although not substantially. It is likely that a longer follow-up period and larger sample would reveal more meaningful changes from pre- to post-test.