Research highlights the high rates and deleterious outcomes of teen dating and sexual violence (DSV), underscoring the critical role of prevention. School personnel have an important role in preventing DSV among teens. The purpose of this study was to explore the rates and correlates of school personnel's opportunity and actions to intervene in situations of teen dating and sexual violence. Participants were 1,150 high school personnel from twenty-five schools recruited via e-mails, flyers, and staff meetings. Results showed that 65.4 percent of school personnel had the opportunity to intervene in at least one type of DSV situation during the past year, and 37.4 to 80.9 percent of school personnel (depending on the type of situation) engaged in positive bystander action when given the opportunity. Further, 47.1 percent of school personnel talked to teens about how to get help if they were experiencing DSV, and 72.3 percent talked to teens about how to have healthy relationships. In general, greater DSV knowledge and efficacy and fewer barriers to intervention in situations of DSV were related to greater bystander opportunity and action. However, for some types of situations (e.g., couples physically fighting), few if any correlates emerged, suggesting the need for future research that includes a more comprehensive set of correlates of bystander opportunity and action in situations of DSV. These findings underscore the critical need for DSV-specific bystander intervention training for high school personnel that helps them recognize situations of DSV and equips them with skills to respond effectively.