This study examines the interactive effects of background factors and personality/attitudinal and perceived environmental dimensions on adolescent drug behavior. Data were collected during home interviews using a structured interview schedule. The sample consisted of 403 British West Indian black, American black, and white adolescents, ranging in age from 13 to 17. Results suggested that two processes, nonconformity to conventional middle class values at both the personality/attitudinal and institutional level, and modeling of familial and peer drug use account in large part for adolescent drug behavior. The majority of correlates of adolescent drug behavior were similar in different sex, age, and ethnic groups.