AT THE INCEPTION OF THE MODEL EVALUATION PROJECT, 13 PROJECTS IN MICHIGAN WERE IDENTIFIED AS FALLING WITHIN THE YOUTH SERVICE BUREAU (YSB) CATEGORY. THE SPECIFIC OBJECTIVES OF THESE BUREAUS WERE IDENTIFIED AS EARLY INTERVENTION IN THE LIVES OF DEVIANT YOUTH TO REDUCE THE NUMBER REFERRED TO JUVENILE COURT, THE PROVISION OF APPROPRIATE INTERVENTION FOR YOUTH DISPLAYING CRIMINAL BEHAVIOR, AND THE ESTABLISHMENT OF A COORDINATING AGENCY FOR JUVENILES TO ACCEPT REFERRALS FROM LAW ENFORCEMENT AGENCIES, SCHOOLS, COURTS, COMMUNITY AGENCIES, PARENTS, AND YOUTHS. AN EVALUATION MODEL WAS DEVELOPED WHICH FOCUSED ON COMMUNITY IMPACT; PROGRAM OPERATION, THE EFFECT ON TARGET YOUTH, AND THE ORGANIZATIONAL STRATEGY. IN GENERAL, THE CONCEPT OF INTENSIVE EVALUATION WAS DIVIDED INTO TWO EQUALLY IMPORTANT ASPECTS: EFFECT AND PROCESS. THE FIRST COMPONENT OF THE EVALUATION FOCUSED ON YSB'S EFFECTIVENESS IN REDUCING CRIME IN THE SPECIFIC JURISDICTIONS AND DIVERTING YOUTH FROM THE JUVENILE JUSTICE SYSTEM. THE PRIMARY METHODOLOGICAL APPROACH CONSISTED OF A TIME-SERIES ANALYSIS OF OFFICIAL STATISTICS. THE FINDINGS PROVIDE NO SYSTEMATIC EVIDENCE THAT THE ESTABLISHMENT OF YOUTH SERVICE BUREAUS CONTRIBUTED TO EITHER A REDUCTION IN CRIME OR THE DIVERSION OF JUVENILES FROM THE FORMAL JUVENILE JUSTICE SYSTEM. THE FINAL SEGMENT OF THE EVALUATION FOCUSED ON THE POTENTIAL EFFECT OF YSB'S ON THE POLICE DECISIONMAKING PROCESS AS CONCERNS THE DISPOSITION OF JUVENILE CASES. THIS INVOLVED DRAWING A SAMPLE OF POLICE DECISIONS FOR THE YEAR PRIOR TO INITIATION OF EACH OF THE BUREAUS UNDER STUDY AND FOR TWO YEARS FOLLOWING THE IMPLEMENTATION OF EACH PROJECT. AN AUTOMATIC INTERACTION DETECTOR PROCEDURE USED TO ANALYZE THE DATA. THE ANALYSIS DID NOT REVEAL ANY SUBSTANTIAL SHIFT IN THE POLICE DECISIONMAKING THAT COULD BE ATTRIBUTED TO THE ESTABLISHMENT OF THE YSB'S. APPENDED MATERIALS INCLUDE SAMPLES OF THE EVALUATION INSTRUMENTS. A BIBLIOGRAPHY IS PROVIDED, AS ARE TABULAR DATA. (RCB)