STUDY SUBJECTS INCLUDED 239 REFERRED AND NONREFERRED JUVENILES APPREHENDED BY THE POLICE. THE EXPERIMENTAL SUBJECTS WERE REFERRED BY THE POLICE TO THE YOUTH SERVICES SYSTEM (YSS), A PROGRAM FOR ASSESSING JUVENILE OFFENDER NEEDS AND REFERRING OFFENDERS TO APPROPRIATE AGENCIES. EXPERIMENTAL SUBJECTS WERE REFERRED IN AUGUST AND SEPTEMBER OF 1973. CONTROL SUBJECTS WERE APPREHENDED BY THE POLICE IN AUGUST AND SEPTEMBER OF 1972 BUT WERE NOT REFERRED TO THE YSS BECAUSE IT WAS NOT FUNCTIONING AT THAT TIME. THE TWO GROUPS WERE MATCHED ON EIGHT BACKGROUND VARIABLES. THE EXPERIMENTAL GROUP WAS DIVIDED INTO THOSE WHO RECEIVED A SIGNIFICANT AMOUNT OF SERVICE FROM REFERRAL (77) AND THOSE WHO RECEIVED RELATIVELY LITTLE SERVICE (72). FOR EACH SUBJECT, INFORMATION WAS GATHERED FROM YSS RECORDS, THE POLICE, AND THE PROBATION DEPARTMENT. YSS RECORDS PROVIDED INFORMATION ON THE AMOUNT OF SERVICE EXPERIMENTAL SUBJECTS RECEIVED; POLICE RECORDS INDICATED THE AMOUNT OF RECIDIVISM FOR EACH SUBJECT IN THE FIRST QUARTER YEAR, THE SECOND QUARTER YEAR, AND THE TOTAL 6 MONTHS AFTER THE REFERRING OFFENSE; AND INFORMATION ON THE OUTCOME OF FAMILY COURT PETITIONS WAS OBTAINED FROM THE PROBATION DEPARTMENT. RESULTS SHOWED THAT EXPERIMENTAL SUBJECTS HAD LESS RECIDIVISM THAN CONTROLS IN THE SECOND QUARTER YEAR FOLLOWUP. COMPARED WITH CONTROLS, EXPERIMENTAL SUBJECTS TENDED TO HAVE FAMILY COURT PETITIONS ADJUSTED AT INTAKE, THUS AVOIDING A COURT APPEARANCE. IT WAS FOUND THAT FIRST OFFENDERS RECEIVING RELATIVELY FEWER REFERRAL SERVICES HAD LESS RECIDIVISM THAN FIRST OFFENDERS RECEIVING SIGNIFICANT SERVICES, AND MINORITY GROUP MEMBERS RECEIVING FEWER SERVICES HAD LESS RECIDIVISM THAN MINORITY GROUP MEMBERS RECEIVING MORE SERVICES. IT IS CONCLUDED THAT THE YSS DEMONSTRATED A POSITIVE EFFECT ON PREVENTION OF RECIDIVISM AND DIVERSION FROM COURT. THE DIFFERING RECIDIVISM RATES BETWEEN THE TWO GROUPS RECEIVING REFERRAL SERVICES, HOWEVER, INDICATES THAT THE PROGRAM MAY HAVE BEEN FUNCTIONING MORE AS A TREATMENT SERVICE THAN AS PREVENTIVE INTERVENTION, WHILE SIGNIFICANT AMOUNTS OF SERVICE MAY HAVE LABELED THE FIRST OFFENDER AS DELINQUENT AND THUS CONTRIBUTED TO THE ACTING OUT OF THAT IDENTITY. TABULAR DATA ARE PROVIDED, ALONG WITH REFERENCES. (AUTHOR ABSTRACT MODIFIED--RCB) (AUTHOR ABSTRACT MODIFIED--RCB)