SUCH METHODS AS PRE- AND POST-TREATMENT PERSONALITY TEST COMPARISONS, FOLLOW-UP INTERVIEWS, AND SIMPLE COUNTS OF RECIDIVISM HAVE ALL BEEN USED TO MEASURE EFFECTIVENESS OF CORRECTIONAL PROGRAMS. HOWEVER, MEASURES OF RECIDIVISM TEND TO IGNORE 'IMPROVEMENTS' SUCH AS INVOLVEMENT IN LESS SERIOUS OFFENSES, WHILE FOLLOW-UP INTERVIEWS ARE DIFFICULT TO OBTAIN IN MANY CASES. THE AUTHORS DESCRIBE A NEW MEASURE OF PROGRAM SUCCESS WHICH MAY OVERCOME SOME OF THE DIFFICULTIES INHERENT IN EARLIER MEASURES. IN THIS PROGRAM REHABILITATION INDEX, PROGRAM EFFECTIVENESS IS MEASURED BY COMPARING THE AVERAGE SEVERITY OF A DISCHARGED INMATE'S FOLLOW-UP OFFENSES TO THE AVERAGE SEVERITY OF HIS ORIGINAL OFFENSE. A CRIME SERIOUSNESS SCALE PROVIDING NUMERICAL VALUES FOR VARIOUS CRIMES IS USED TO CALCULATE THESE MEASURES...DMC