Studies demonstrate that peer-to-peer teasing, bullying, and sexual harassment commonly occur in schools. Teasing, bullying, and sexual harassment victimization can cause considerable distress for students. Bullying and sexual harassment have been studied separately for the most part, and few studies of teasing exist. Research on bullying among adolescents has been more plentiful and sophisticated than that on sexual harassment and teasing. Bullying research has included use of data from peers, teachers, and parents; examination of bully and victim characteristics; and investigation of a broad array of psychosocial outcomes. Connections among teasing, bullying, and sexual harassment, however, have not been examined empirically among adolescents. Furthermore, studies of teasing and sexual harassment rarely have moved beyond self-report of prevalence rates, categorization of content (e.g., name calling, sexual pushing, or shoving), and self-reported educational and emotional correlates. The relation of teasing and sexual harassment to social competence has not been investigated. Given the high prevalence of teasing, bullying, and sexual harassment, and the profound and long-lasting devastation they can cause, it is imperative that they be better understood. Information regarding the interrelation of teasing, bullying, and sexual harassment could aid in the creation of policies designed to prevent all forms of peer victimization. The study proposed herein is designed to compare teasing, bullying, and sexual harassment, using adolescents own definitions of each, their responses to questions asking about specific behaviors that have been identified in the literature as typical of each, and peer reports of adolescents perpetration and victimization. The study includes