Findings in these studies are sometimes contradictory, but this may be due to the differences in measures and in samples. The following convergent views emerge from the literature: (1) In adolescence, general forms of drug use and delinquency are not causally related, but are spuriously related because they are both types of deviant activity in which adolescents engage; (2) Adolescents are heterogeneous in terms of their levels of substance use and delinquency and the co-occurrence of both behaviors; (3) The majority of adolescents have no or only minor delinquency involvement regardless of the extent of their substance use; and, (4) Peer group influences are the best predictors of delinquency and drug use. There are several areas that have not been thoroughly addressed when exploring the drug-delinquency connection. These include differential opportunity, reinforcements derived from behaviors, nonsocial reinforcers, and the motivations for and the expectations of delinquent behavior. 7 notes, 126 references.