IN OCTOBER 1972, THE UNITED STATES PAROLE COMMISSION FIRST USED PAROLE DECISIONMAKING GUIDELINES ON AN EXPERIMENTAL BASIS. THE GUIDELINES BECAME FULLY OPERATIONAL IN JUNE 1974. THE GUIDELINES ARE DESIGNED TO LIMIT DISCRETIONARY DECISIONS WITHOUT ELIMINATING INDIVIDUAL CASE CONSIDERATIONS. THE GUIDELINES MATRIX PRESUMES GOOD INSTITUTIONAL BEHAVIOR AND PROVIDES A METHOD FOR DETERMINING PAROLE DECISIONS BASED ON SERIOUSNESS OF THE PRESENT OFFENSE AND PAROLE PROGNOSIS. DECISIONS OUTSIDE OF THE GUIDELINES ARE PERMITTED IF ACCOMPANIED BY WRITTEN EXPLANATIONS. DATA COLLECTED BY REGIONAL RESEARCH RECORDERS REVEALED AN INCREASE IN THE PROPORTION OF CASES RATED AS VERY HIGH IN SEVERITY THAT ARE APPLYING FOR PAROLE. A LOOK AT SPECIFIC OFFENSE CATEGORIES PROVED INFORMATIVE. MEAN SEVERITY LEVELS FOR ROBBERY REMAINED CONSTANT, WHILE MEAN SEVERITY RATINGS FOR POSSESSION WITH INTENT TO DISTRIBUTE OR SELL HARD DRUGS AND FOR FIREARMS OFFENSES SIGNIFICANTLY INCREASED. THESE INCREASES, HOWEVER, ARE ATTRIBUTED TO A CHANGE IN COMMISSION POLICY REGARDING THE SERIOUSNESS OF THESE OFFENSE CATEGORIES. AN EXAMINATION OF PAROLE PROGNOSIS REVEALED NO SIGNIFICANT TRENDS. THE PURPOSE OF THIS ANALYSIS IS TO DESCRIBE CHANGES IN THE TYPES OF OFFENDERS BEING HEARD BY THE COMMISSION AND TO ASCERTAIN THE EFFECTS OF CHANGES IN POLICY. HOWEVER, SUCH ANALYSIS COULD BE USED ALSO AS AN AID IN FORECASTING LENGTH OF INCARCERATION OF INMATES. IT IS SUGGESTED THAT EVEN A SMALL IMPROVEMENT IN THE CURRENCY OF POPULATION LEVEL FORECASTING WOULD AID PRISON PLANNING. (MLC)