The purpose of the current study was to use data from multiple sources to examine aspects of implementation (i.e., program fidelity, barriers and enablers to implementation, and acceptability) of a bystander-focused violence prevention curriculum. Four public high schools and one community-based agency in upper New England participated in the current project in which teachers, agency staff, or students were trained to facilitate a bystander-focused relationship abuse and sexual assault prevention curriculum. Survey and interview data were collected from facilitators (N = 62), survey data were collected from program recipients (i.e., adolescents; N = 192), and fidelity and process observations were collected from research staff who observed sessions (N = 8). Results indicated that on the whole facilitators were pleased with the training they received, the program content, and the delivery format. Program fidelity was determined to be generally high; barriers to fidelity included technological issues, running out of time, and unintentionally forgetting content. Students generally rated the program positively, although they suggested areas for improvement, including having more interactive and less repetitive content. These findings can be used by other researchers, schools, and practitioners implementing manualized classroom-based prevention programs.