Sexual assault is a serious public health issue that is especially problematic on college campuses. To combat sexual violence on college campuses prevention programs have been instituted by many universities. One such prevention program, the Green Dot program, works to teach students what constitutes sexual violence and how to prevent it by increasing bystander intervention. The current study examined the effectiveness of Green Dot at a large southeastern university. The Theory of Planned Behavior (TPB) was used as the theoretical framework. TPB examines how efficacy, attitudes, and norms influence behavior. Students were recruited to participate in the Green Dot program via the Women’s Center. Green Dot participants were asked to complete a survey before Green Dot, one-week after, and a one-month follow-up. Hierarchical linear modeling (HLM) was used to examine the data longitudinally. It was hypothesized that participants in Green Dot training would increase bystander behaviors, efficacy, and attitudes, as well as social sexual norm perceptions. Results using HLM indicate that there were significant differences between the comparison and experimental group, such that the comparison group has higher bystander efficacy scores. Additionally, men and women differed significantly on the perceived social sexual behaviors of the average male on campus, such that men had more positive perceived sexual norms for the average male on campus. Although small findings, this research is important in understanding how to safely intervene in possible instances of power-based violence, which is critical in preventing sexual violence