It was found that gang and club boys differ significantly on five of the personality factors. Club boys were found to be more assertive, more exuberant, and more realistic. Gang boys show more manic smartness and less self-realization. An examination of possible relationships between these variables and types of delinquent behavior found that three factors (assertiveness, altertness, and stolidness) do show significant differences between gang boys engaged in different types of delinquent behavior. However, no simple linear relationships were found between personality factors and delinquent behaviors in gangs. Several hypotheses drawn from theories of personality and of gang delinquency may be useful in explaining the results of this study. Five tables and 17 references are included. (Author abstract modified)