Adolescent antisocial behavior is an issue of major concern and is a significant cost to the community. However, few longitudinal Australian studies have measured the rates and types of antisocial behavior at multiple age points from early to late adolescence. This study was a collaboration between Crime Prevention Victoria and the Australian Institute of Family Studies using data from the Australian Temperament Project (ATP) describing and analyzing patterns of antisocial behavior from 13 to 18 years among a sample of Victorian adolescents. The study focused on the types and extent of antisocial behavior for adolescents’ ages 13-14, 15-16, and 17-18 years exploring differing across time patterns of such behavior. Results indicate some engagement in antisocial behavior was found to be common. Some antisocial acts, such as alcohol and cigarette use and skipping school were so prevalent that they seemed normal. Overall, most adolescents were involved in a limited number and range of antisocial acts. While occasional involvement in minor antisocial acts was common, engagement in more serious acts was unusual and atypical. Figures and references