Swedish adolescents (N = 1,760) completed a Web-based questionnaire. A measure of bullying and measures of peer aggression were compared in order to elucidate the unique contribution of each measure as well as the overlap: 13 percent of students who experienced peer victimization reported only bullying, 44 percent reported only repeated peer aggression, and 43 percent reported both. Concordance was further elucidated by phi-square coefficient tests revealing that 18 percent of the variance in either measure was accounted for by the other measure. Given recent research showing similar associations with mental health for bullying and peer aggression victimization, it is suggested that questions about peer aggression as well as bullying should be used simultaneously in order to capture the prevalence and full magnitude of peer victimization. Abstract published by arrangement with Taylor and Francis.