THE STUDY WAS UNDERTAKEN TO DETERMINE IF THE OPEN PRISON IS MORE SUCCESSFUL IN ALTERING BEHAVIORAL PATTERNS AND STIGMATIZATION AND THUS IN REDUCING RECIDIVISM, AND THE SELECTION CRITERIA FOR PRISONERS SENT TO THE OPEN PRISONS WERE STUDIED. RELEASED FROM FOUR DIFFERENT TYPES OF PRISONS (OPEN, PARTIALLY OPEN, MEDIUM SECURITY, MAXIMUM SECURITY), 175 EX-OFFENDERS WERE SURVEYED AND CLASSIFIED ACCORDING TO NEW OFFENSES (3 YEARS AFTER RELEASE), ALTERABLE BEHAVIORAL CHARACTERISTICS, AND PERMANENT BIOGRAPHICAL CHARACTERISTICS. RESULTS SHOWED THAT THE OPEN PRISON TENDED TO DISCOURAGE THE HARDENING OF CRIMINAL BEHAVIOR. FURTHERMORE, THOSE OFFENDERS WHO WERE PRIVILEGED IN BEING SENT TO THE OPEN FACILITIES EXPERIENCED A POSITIVE COURT REACTION WHEN INVESTIGATED OR TRIED FOR A NEW OFFENSE; PREVIOUS TERMS OF CONFINEMENT DID NOT APPEAR TO AFFECT A PRISONER'S SELECTION FOR THE OPEN PRISON. OTHER CRITERIA NOT DISCOVERED WERE APPARENTLY INVOLVED. RESULTS ALSO INDICATED THAT THE LENGTH OF CONFINEMENT IN CLOSED PRISONS AFFECTS RECIDIVISM (THE LONGER THE PERIOD OF IMPRISONMENT, THE HIGHER THE RATE OF RECIDIVISM) AND THAT THOSE WHO HAD NO FAMILY AT HOME AND THOSE WHO RECEIVED FEW VISITS DURING CONFINEMENT WERE MORE PRONE TO RECIDIVISM. BECAUSE OF THE LIMITED NUMBER OF PRISONERS STUDIED, THESE RESULTS CAN ONLY SERVE AS WORKING HYPOTHESES FOR A LARGER INVESTIGATION. EXTENSIVE STATISTICAL CHARTS, FOOTNOTES, AND A BIBLIOGRAPHY ARE INCLUDED. --IN GERMAN. (SAJ)