The initiative of this program is to prevent teen dating violence (TDV) by helping 11-to-14-year-old male and female youth develop healthy and safe relationship knowledge and skills.  RTI developed a rigorous, quasi-experimental evaluation design to evaluate whether this initiative has impacted TDV. The evaluation included two components: (1) an outcome evaluation to assess the effectiveness and implementation of the Start Strong TDV prevention initiative and (2) a policy evaluation to assess the adoption, implementation, and sustainability of policy efforts. As part of the outcome evaluation, RTI examined the effectiveness of the initiative through collection of student and teacher data on key outcomes (i.e., TDV perpetration and victimization), as well as critical mediators that may underlie hypothesized changes (i.e., conflict management skills, anger management skills, gender stereotyping, dating violence norms).