The interrelation of childhood aggression, early and late adolescent delinquency, and drug use was explored. Data were obtained for the subjects when they were 5-10 years old. Follow-up interviews were conducted when the subjects were between 13-18 years old and again when they were 15-20 years old. A LISREL analysis of the three waves of data indicated that childhood aggression is a precursor of adolescent drug use and delinquency, and that early adolescent drug use is correlated with contemporaneous delinquency as well as with later drug use and delinquency.