The most basic premise in the current understanding of delinquency is that adolescent crime involves a developmental progression from relatively minor to more serious antisocial behaviors. Contemporary thought suggests a comprehensive understanding of delinquency requires an explanation of such antisocial behaviors as temper tantrums and noncompliance during early childhood before the age when criminal acts are likely to occur. The realization that early behavioral manifestations of later criminal conduct likely become apparent prior to adolescence has placed new emphasis on the role of the family in explaining delinquency. Family interactions involve reciprocal influences in parent and child behaviors that affect the probability of child misconduct and disruptions in effective childrearing practices. The matching law of behavior approach to social learning and conditioning describes choice behavior without assuming a highly rational organism capable of weighing long-term costs and benefits of a particular act. The matching law applies to human behavior in social situations, provides important insights about processes through which individual children and adolescents develop a propensity for conduct problems, and assumes variations in environmental contingencies related to reinforcement and punishment heavily influence choices regarding socially accepted versus antisocial behavior. Theoretical dimensions of the matching law approach to antisocial behavior are discussed, antisocial and delinquent behavior is viewed as a developmental progression, and reciprocal influences in deviant trajectories and differences in developmental trajectories of delinquency are examined. 67 references and 3 figures