THE BASIC THEORETICAL ORIENTATION AND FRAMEWORK FOR THIS STUDY WAS DERIVED FROM SOCIAL CONTROL THEORY. AN ACTUAL REHABILITATION PROGRAM INVOLVING VOLUNTEERS, 'VOLUNTEERS IN PROBATION AND PAROLE' OF LANCASTER COUNTY WAS UTLIZED. TWO GENERAL PROBLEMS WERE RESEARCHED: THE COMPARATIVE RECIDIVISM OF PROBATIONERS AND PAROLEES WHO WERE MATCHED WITH VOLUNTEERS VERSUS THOSE RECEIVING SUPERVISION ONLY BY A PROBATION OFFICER, AND AN ASSESSMENT OF THE PERSONALITY AND SOCIALIZATION CHANGES OF THE PROBATIONERS AND PAROLEES MATCHED WITH VOLUNTEERS. RECIDIVISM OF THE SUBJECTS WAS MEASURED BY MEANS OF A THREE-WAY INDEX OF RECIDIVISM WHICH TOOK INTO ACCOUNT THE ABSOLUTE NUMBER OF VIOLATIONS OR NEW CRIMINAL OFFENSES, THE SEVERITY OF THE CRIMINAL OFFENSE, AND THE NUMBER OF MULTIPLE VIOLATIONS OR OFFENSES COMMITTED BY ONE INDIVIDUAL. PERSONALITY CHANGES WERE MEASURED BY MEANS OF A QUESTIONNAIRE WHICH TESTED FOR GROWTH AND DEVELOPMENT IN 16 INTERRELATED ASPECTS OF PERSONALITY OVER SIX MONTHS OF INTERACTION WITH A VOLUNTEER. THE RESULTS SUPPORTED THE USE OF VOLUNTEERISM AS A TREATMENT STRATEGY IN THE CRIMINAL JUSTICE SYSTEM. PROBATIONERS AND PAROLEES MATCHED WITH VOLUNTEERS EXHIBITED LOWER RATES OF RECIDIVISM. THE RESULTS OF THE PERSONALITY QUESTIONNAIRE SHOWED THAT VOLUNTEERS ALSO HAD A POSITIVE IMPACT ON PERSONALITY FACTORS; HOWEVER, IT WAS CONCLUDED THAT THE SUBJECTS HAD ADJUSTED THEIR OUTWARD BEHAVIOR MORE READILY THAN THEIR INTERNAL ATTITUDES.