IN 1974, OVER 800 YOUTHS IN COOK COUNTY HAD RECORDS OF DELINQUENCY FOR VIOLENT OFFENSES. OVER 200 OF THESE DELINQUENTS WERE SENT TO THE DEPARTMENT OF CORRECTIONS; THE REMAINING 606 FORMED THE BASE GROUP FOR THE STUDY. MEMBERS OF THE BASE GROUP WERE TRACED FROM 1974 THROUGH MARCH 1977 FOR FINDINGS OF NEW OFFENSES. OF THESE JUVENILES, COMPOSING THE BASE GROUP, 84 WERE FOUND TO HAVE COMMITTED NEW OFFENSES, VIOLENT OR NONVIOLENT. THE OVERALL RECIDIVISM RATE (14 PERCENT) WAS LOWER FOR OLDER JUVENILES. FOR MORE THAN HALF OF THE 84 RECIDIVISTS, THE NEW FINDING WAS FOR VIOLENT OFFENSES. ELEVEN RECIDIVISTS HAD FINDINGS FOR MORE THAN ONE OFFENSE, RESULTING IN A MULTIPLE RECIDIVISM RATE OF 2 PERCENT FOR THE BASE GROUP. ONLY 3 PERCENT BECAME INVOLVED IN OFFENSES MORE SERIOUS THAN THAT FOR WHICH THEY WERE REFERRED ORIGINALLY. OF THE JUVENILES IN THE BASE GROUP, 368 HAD HAD AT LEAST ONE PETITION PRIOR TO 1974. THOSE WHOSE 1974 FINDING WAS THEIR FIRST PETITION WERE CALLED FIRST OFFENDERS, WHILE THOSE WHO HAD AT LEAST ONE EARLIER PETITION BEFORE THE 1974 FINDING WERE CALLED REPEATERS. THE RECIDIVISM RATE WAS 12 PERCENT FOR FIRST OFFENDERS AND 15 PERCENT FOR REPEATERS. IT WAS HIGHEST AMONG REPEATERS AGED 9 TO 13 YEARS COMPARED WITH FIRST OFFENDERS IN THE SAME AGE GROUP AND OLDER YOUTHS. THE YEARLY RECIDIVISM RATE, I.E., THE PROPORTION OF THE BASE GROUP COMMITTING NEW OFFENSES IN A GIVEN YEAR, INCREASED OVER THE YEARS STUDIED. IF A NEW OFFENSE WAS COMMITTED WHILE THE YOUTH WAS ON PROBATION, THE RECIDIVISM WAS LESS VIOLENT DURING THE FIRST 5 MONTHS OF PROBATION THAN LATER. AFTER PROBATION, RECIDIVISM WAS LESS VIOLENT IF PROBATION HAD LASTED ONE YEAR THAN IF IT HAD BEEN SHORTER. FINDINGS ARE REPRESENTED GRAPHICALLY, AND APPENDED TABLES DOCUMENT RESEARCH FINDINGS.