STANDARDIZED QUESTIONNAIRES WERE SUBMITTED TO THE STUDY GROUP OF 36 MALE TREATED OFFENDERS AND TO A CONTROL GROUP OF 56 INMATES FROM TWO ORDINARY WEST GERMAN CORRECTIONAL FACILITIES; STUDY AND CONTROL GROUPS WERE QUESTIONED TWICE WITH A 9-MONTH PERIOD BETWEEN EACH INTERVIEW. THE FACTORS UNDER CONSIDERATION IN THE PERSONALITY EVALUATION WERE NERVOUSNESS, DEPRESSION, IRRITABILITY, INHIBITIONS, EMOTIONAL INSTABILITY, MASCULING ROLE CONCEPT, SOCIAL IMAGE, AND SELF-CONTROL) WHILE THE PERSONALITY VALUES FOR NON-TREATED OFFENDERS REMAINED UNCHANGED OVER THE 9-MONTHS PERIOD. CHANGES IN SOCIAL CONTACTS WERE EVALUATED IN 3 ASPECTS: (1) CONTACTS WITH THE OUTSIDE WORLD (MEASURED IN THE NUMBER OF LETTER CONTACTS AND VISITORS, (2) CONTACTS TO FELLOW INMATES (MEASURED IN THE NUMBER OF INMATES A PRISONER CONSIDERED HIS FRIENDS), AND (3) CONTACTS TO CORRECTIONAL PERSONNEL (MEASURED IN THE NUMBER OF STAFF MEMBERS A PRISONER CONSIDERED HIS FRIENDS). WHILE THE TREATED OFFENDERS IMPROVED THEIR CONTACTS TO THE OUTSIDE WORLD MORE THAN NON-TREATED OFFENDERS, THE RESULTS CONCERNING INMATE CONTACTS--SURPRISINGLY--DIFFERED VERY LITTLE IN BOTH GROUPS. WHILE THE OFFENDERS FROM THE SOCIAL THERAPEUTIC INSTITUTION HAD ESPECIALLY GOOD RELATIONS TO THEIR THERAPISTS, THEIR RELATIONS TO OTHER CORRECTIONAL PERSONNEL NEEDED IMPROVEMENT. THE STUDY CONCLUDES THAT SOCIAL THERAPEUTIC TREATMENT HAS A POSITIVE INFLUENCE ON OFFENDER SOCIALIZATION BUT EMPHASIZES THE NEED FOR ADDITIONAL STUDY. A BIBLIOGRAPHY AND THE STATISTICAL DATA ARE INCLUDED. --IN GERMAN.