The focus of this thesis lies on the professionalization and training of trainers, who are engaged in the violence prevention work with adolescents. The primary idea of creating a training plan based on an existing concept was ? influenced by empirical results and a literature research ? further developed to a clear focus on competencies. Based on results of the Delphi survey method of interviewing the experts, an adaptation of the basic concept was implemented, a detailed training plan was created and a competence profile was rendered. Competences necessary for a professionalization of trainers are investigated and analyzed. In addition, an exemplary model of a training plan is presented. The thesis presented contributes to the professionalization of violence prevention work.