The focus was on youths ages 10-16. Data were gathered from two police force areas, one in a Midlands county and the second in two London boroughs. Information came from police files, social service agencies, and detailed interviews with 74 offenders. The analysis considers the backgrounds, criminal histories, educational experiences, contact with welfare, and alcohol and drug use by these young offenders. Results revealed that the most common offenses were traffic, nonresidential burglary, theft form shops, and automobile theft. Violence, sex offenses, and other serious violent crimes were extremely rare. The self-reports from the interviews suggested high rates of unrecorded crime of the same types as in the official data. Alcohol and drug use were high, and half of the 74 interviewed recidivists had had some sort of counseling. Findings did not indicate a distinct group of very frequent offenders and indicated that the persistent offenders were not disproportionately involved in serious offending. Figures, tables, appended instrument and tables, and 79 references