The core group of the Junior Outlaws consisted of 18 white Catholic boys between 14 and 16 years of age. During the study period, seven boys became involved with official agencies as a result of delinquent acts. In addition, group members committed numerous criminal acts for which no official action was taken. Data were obtained by a trained social worker who maintained intensive and continuous contact with the Junior Outlaws in their own cultural environment over a 2.5-year period. Information was recorded on aggressive acts to evaluate targets of aggressive behavior, forms in which aggression was expressed, the relationship between aggressive behavior and its social and interactional context, and the content of aggressive statements. Results indicated that most aggressive actions of the Junior Outlaws were directed at one another. The Junior Outlaws manifested an extremely narrow range of aggressive tactics, sharply limited in terms of target, form, and emotional intensity. Acts of physical aggression were rare, the social world of group members was narrowly defined, and aggression was primarily a characteristic of group interaction. Aggressive expression within the Junior Outlaws helped to produce and maintain group cohesion and was not judged to be pathologically abnormal. Footnotes and tables