The study sought to combine approaches to the study of street corner groups and patterns of delinquency. Data were obtained through field gang observations, weekly interviews with detached workers, and a survey-type interview of male gang members. Data were also collected using sociometric instruments and laboratory assessment of intelligence, values, motivation, and personality characteristics. Semantic differential data suggested that black and white, lower class gang and nongang boys and middle-class boys did not differ in their recognition of the moral validity and the legitimacy of some middle-class values. Gang boys, however, evaluated illegitimate images more highly than did other boys, and their behavior was inconsistent with middle class values. This discrepancy is examined in terms of the operation of "aleatory" factors peculiar to lower class settings and group processes. Further study is suggested to assess competing delinquency theories. 40 footnotes