THIS VOLUME DEALS ONLY WITH JUVENILES APPREHENDED BY THE POLICE AND CONSEQUENTLY CAUGHT UP IN THE JUVENILE JUSTICE SYSTEM. THE STUDY INVOLVED VISITS TO PROGRAMS AND PROJECTS DEALING WITH DELINQUENT YOUTH AND THE ANALYSIS OF OVER 500 COURT RECORDS OF JUVENILES IN THE NEW YORK METROPOLITAN AREA. THE SCOPE OF THE DELINQUENCY PROBLEM IS DETERMINED BY ANALYZING AND INTEGRATING ARREST DATA, SELF-REPORT SURVEYS, COHORT STUDIES, AND A VERA INSTITUTE STUDY. THE CHARACTERISTICS OF VIOLENT DELINQUENTS ARE EXAMINED AS THEY RELATE TO PATTERNS OF DELINQUENCY AND VIOLENCE, SEX, AGE, RACE, FAMILY STRUCTURE, SOCIOECONOMIC STATUS AND SOCIAL ENVIRONMENT, EDUCATION AND LEARNING, PSYCHIATRIC CHARACTERISTICS, AND PHYSICAL HEALTH. THE RELATIONSHIP BETWEEN JUVENILE AND ADULT CRIMINALITY ALSO IS DISCUSSED BRIEFLY. OFFICIAL RESPONSES TO VIOLENT DELINQUENTS ARE ASSESSED, INCLUDING POLICE AND COURT PROCESSING, AND COURT OUTCOME AND DISPOSITION. THE TREATMENT OF VIOLENT DELINQUENTS, VARIETIES OF TREATMENT, SELECTING TREATMENT MODES, AND TREATMENT IN THE PUNISHMENT CONTEXT ARE EXAMINED. THOUGHTS ON STRATEGIES FOR PREVENTING JUVENILE VIOLENCE ARE PRESENTED CONCERNING PREVENTIVE TREATMENT, INCAPACITATION, DETERRENCE, AND TARGET HARDENING. CONCLUSIONS AND RECOMMENDATIONS ARE PROVIDED REGARDING DATA COLLECTION AND BASIC RESEARCH, EXPERIMENTAL INTERVENTION PROGRAMS, AND CONTINUOUS CASE MANAGEMENT. APPENDED MATERIALS INCLUDE A SUMMARY OF DATA COLLECTION IN THE VERA INSTITUTE STUDY, THE VERA INSTITUTE STUDY RESEARCH INSTRUMENT, THE SELLIN-WOLFGANG SERIOUSNESS SCALE, THREE MODEL PROGRAMS, AND A SELECTED BIBLIOGRAPHY. AN INDEX, A LIST OF TABLES, AND FIGURES ARE PROVIDED.