In general, juvenile delinquents commit a large number of offenses without any particular pattern. The acts are usually vandalism or minor theft and are generally undertaken during a relatively limited time period. The types of delinquents described are aggressive, nonsocialized juveniles; self-centered, complaisant delinquents; psychopathic delinquents; and otherwise normal delinquents acting out their interior agitation. The sample of conventional delinquents is analysed and compared to the sample of delinquent juveniles. Results indicate that true juvenile delinquents commit more serious offenses and more diverse offenses than do conventional juveniles. The distinguishing characteristics of delinquent juveniles are social maladjustment, rejection of authority, hostility in interpersonal relationships, and poor relationships with mothers and school. The groups most enmeshed in delinquent activities can thus be easily differentiated from the other groups. Juveniles can be classified according to the intensity of problems: a continuum of inadaptation shows the gradation of negative characteristics which affirm delinquent conduct. On the scale, three levels of adaptability can be differentiated: relatively good social adjustment despite developmental deficits, marginality, and criminality. These results suggest that individuals responsible for the treatment of juveniles should obtain thorough, accurate social and psychological information on juveniles to be treated. Treatment decisions can then be made by measuring individual delinquents on the inadaptation scale. Juveniles in the zone of relatively good socialization can be treated in community programs without formal intervention; marginal juveniles can be treated through social rather than legal intervention; and court intervention is necessary for juvenile delinquents with continuing serious problems. Tables, a 26-item bibliography, and an appendix with a list of social variables are supplied.