The book proceeded from the premise that much delinquency involves participation in a delinquent subculture. The core of this article reviews the principal types of these subcultures, describes their characteristic features, speculates on their origins, indicates the types of research and theoretical work most needed, and suggests hypotheses to be tested or revised by later research. Five delinquent male subcultures are identified. One is the "parent male" subculture, which is nonutilitarian, malicious, negativistic, versatile, and characterized by short-term hedonism and group autonomy. It is the most common type of delinquent subculture in America. A second type of subculture is the "conflict-oriented" subculture, which consists of large gangs with a relatively elaborate organization, in contrast to the small, informal groups of the "parent male" subculture. A third delinquent subculture is the "drug addict" subculture, which centers around the use of narcotic drugs and an associated lifestyle. A fourth subculture is characterized by "semi-professional theft." Participants in this subculture spend much of their time pursuing utilitarian, systematic, and pecuniary crime. The fifth type of delinquent subculture is the "middle-class" delinquent subculture, which arises in response to adjustment problems associated with middle-class socialization and middle-class life situations. Remaining sections of the article discuss determinants of the male subcultures and female delinquent subcultures. 28 references