Rates of physically forced sex to dating violence remain high in college communities (22% of 10,000 female undergraduates disclosed these forms of violence against women (VAW) in the past 12 months (2010-2013). Bystander interventions, recognized as promising violence prevention strategies, are unique in their engagement of all community members to 1) recognize situations that may become violent and 2) learn to safely and effectively intervene to reduce violence risk. Based on their promise, the Campus Sexual Violence Elimination Act (SaVE) now requires all publicly-funded college to provide bystander intervention. With SaVE's policy intervention requiring bystander intervention, a natural experiment has arisen to determine the relative efficacy of students' bystander training across multiple colleges. We propose a quasi-experimental design with fractional factorials to evaluate the relative efficacy of bystander interventions components to reduce violence in college communities. Green Dot will be one of the bystander intervention components evaluated because our group has considerable experience rigorously evaluating Green Dot and we have recently found that this bystander intervention is associated with a 20-40% reduction in VAW in college and high school settings. Aim 1. Compare the relative efficacy of bystander interventions to 1) increase bystander efficacy and behaviors, 2) reduce violence acceptance, 3) reduce violence victimization and perpetration, and 4) increase program cost effectiveness. The three primary bystander groups compared will be: a) exclusively online training, Green Dot (speeches and intensive bystander training), and other skills-based by stander training. Program efficacy data will be obtained from student surveys, campus crime statistics, and surveys with college staff and administrators responsible for selecting and implementing bystander interventions. We will collect data at each college for the full 4 years of the project (~50,000 students annually. Infrastructure provided by the Kentucky Center for Clinical and Translational Science at the University of Kentucky and West Virginia University will support a VAW Research Coordinating Center for all electronic data collection and analyses from 24 recruited colleges, comparing the different bystander interventions. VAW researchers draw from multiple disciplines yet few training programs support this diverse field of highly relevant applied research. Thus, we seek to grow communities of VAW prevention researchers. Researcher communities will form through researcher' engagement with college recruitment, survey design, data collection and analyses. Aim 2. Determine the efficacy of this program to increase VAW prevention research productivity defined as 1) increasing research skills and 2) increasing research communities measured as manuscript submissions, presentations, and publications. This natural experiment will generate new understanding of how and what bystander components work to prevent violence. It will also provide the VAW research community an opportunity to increase our skill-sets and share our experiences with and help grow the next generation of VAW prevention researchers.