In order to assess knowledge of social skills among juvenile delinquents, a sample of 411 adolescent offenders was obtained. The sample consisted of all adjudicated male delinquents aged 12 to 15 admitted to a State training school over a 16-month period of time. Data were obtained on a measure of knowledge of social skills, the Adolescent Problems Inventory (API), along with a variety of measures of personality, behavioral, social, intellectual, and educational skills. The adolescents were divided into three groups: a group competent in knowledge of social skills, a group that was incompetent, and one that was moderately competent. Analyses of variance among these three groups suggested that they differed along a number of dimensions. In particular, the group that had the lowest scores in terms of knowledge of social skills appeared to have a wide variety of behavioral difficulties. The usefulness of social skills assessment in terms of classification is discussed, as are implications for treatment. (Publisher abstract)