These hypotheses focus on 1) type of leisure activity (e.g., sports versus hobbies), 2) with whom the leisure activity is performed, and 3) the extent to which the leisure activity is liked by the respondent. Data from a random sample of 600 adolescents in a major metropolitan area indicate that delinquency is positively related to time spent in 1) unsupervised social activities, 2) leisure activities with peers, and 3) least favorite leisure activities with parents. Delinquency is negatively related to time spent in 1) organized leisure activities, 2) passive entertainment, and 3) noncompetitive sports. These data suggest that future research on delinquency should give more attention to leisure activities. 5 tables, 47 notes. (Author abstract)