THE PAPER DRAWS UPON OFFICIAL DATA COLLECTED DURING TWO INITIAL RESEARCH PHASES AND AN ADDITIONAL 5 YEARS OF DATA COLLECTION. THE SUBJECTS OF THE RESEARCH WERE 971 PHILADELPHIA MALES BORN IN 1945. SPECIAL ATTENTION WAS GIVEN TO CHRONIC OFFENDERS WHO COMMITTED 74 PERCENT OF ALL OFFENSES, MANY OF THEM SERIOUS. TO ESTIMATE THE PREDICTIVE CAPACITY OF SEVERAL OFFENDER AND OFFENSE CHARACTERISTICS, A REGRESSION ANALYSIS WAS PERFORMED. USING VARIABLES FROM THE IMMEDIATELY PRECEDING OFFENSE, THE SERIOUSNESS OF THE NEXT OFFENSE WAS ESTIMATED FOR FOUR OFFENSE TRANSITIONS. RESULTS SHOWED THAT IF INDIVIDUALS CONTINED TO OFFEND, THEIR OFFENSES WOULD BE MORE SERIOUS. THE FINDING THAT A RELATIVELY SMALL NUMBER OF OFFENDERS IS RESPONSIBLE FOR THE HIGH PERCENTAGE AND SERIOUSNESS OF OFFENSES HAS IMPORTANT IMPLICATIONS FOR CRIMINAL JUSTICE OFFICIALS WHO SHOULD CONSIDER SELECTING SUCH OFFENDERS FOR SPECIAL HANDLING. SPECIAL INTERVENTION ON THE BASIS OF ACCUMULATED POLICE CONTACTS AND SUBSEQUENT CONVICTION FOR A SERIOUS FELONY ARE SUGGESTED. NOTES, REFERENCES, AND TABULAR DATA ARE INCLUDED. (MJW)