THIS STUDY ADDRESSED THREE PRIMARY QUESTIONS: (1) ARE SERIOUS OFFENDERS BEING CLASSIFIED ON THE BASIS OF THE VIOLENCE OF THEIR CRIME OR BY THEIR RECIDIVISM IN PROPERTY CRIME; (2) ARE THE JUVENILES CLASSIFIED AS VIOLENT OR HARDCORE LIKELY TO COMMIT ADDITIONAL SERIOUS CRIMES; AND (3) WHAT FACTORS (E.G, AGE, TYPE OF OFFENSE, DISPOSITION) IN A JUVENILE'S COURT RECORD BEST PREDICT FUTURE OFFENSE BEHAVIOR? SELECTION OF THE 10 COUNTIES FOR THE STUDY WAS PERFORMED SO THAT EACH OF THE SEVEN CRIMINAL JUSTICE PLANNING REGIONS, BOTH METROPOLITAN AND OUTSTATE AREAS, AND THE MAIN POPULATION CENTER OF EACH REGION WOULD BE INCLUDED. IT WAS FOUND THAT JUVENILES TYPICALLY DEFINED AS VIOLENT OR HARDCORE WERE OFTEN REPEAT PROPERTY OFFENDERS. DEFINITIONS PRESENTLY IN USE ARE NOT EFFECTIVE IN PREDICTING RECIDIVISM. THE BEST SINGLE PREDICTOR OF REPEAT SERIOUS DELINQUENCY IS AGE. JUVENILES WHO BEGIN WITH STATUS OFFENSES AT A YOUNG AGE ARE NOT THE CAREER CRIMINALS OF THE FUTURE; RATHER, SERIOUS OFFENSES AT AN EARLY AGE MAY BE A GOOD PREDICTOR. IT IS NOT POSSIBLE TO PREDICT WITH A HIGH DEGREE OF CERTAINTY WHICH JUVENILES WILL COMMIT ACTS OF VIOLENCE. IT ALSO APPEARED THAT UNDER CURRENT PRACTICES, COURTS DISPOSITION OF A JUVENILE DOES NOT HAVE ANY SUBSTANTIAL IMPACT ON HIS OR HER SUBSEQUENT DELINQUENT BEHAVIOR. IT IS RECOMMENDED THAT THE CRIMINAL JUSTICE SYSTEM GIVE INCREASED ATTENTION TO THE YOUNGER JUVENILE WHO HAS COMMITTED A FELONY. FINALLY, A FOLLOWUP STUDY USING THIS SAME SAMPLE IS SUGGESTED. TABLES AND BIBLIOGRAPHY ARE INCLUDED. (AUTHOR ABSTRACT MODIFIED)