A RATIONAL DECISION IS DEFINED AS 'THAT DECISION AMONG THOSE POSSIBLE FOR THE DECISIONMAKER WHICH, IN THE LIGHT OF THE INFORMATION AVAILABLE, MAXIMIZES THE PROBABILITY OF THE ACHIEVEMENT OF THE PURPOSE OF THE DECISIONMAKER IN THAT SPECIFIC AND PARTICULAR CASE.' BY THIS DEFINITION, RATIONAL DECISIONMAKING RARELY OCCURS IN THE CRIMINAL JUSTICE SYSTEM. AVAILABLE METHODS OF DIAGNOSIS, CLASSIFICATION, AND PREDICTION ARE INADEQUATE TO PROVIDE MUCH USEFUL GUIDANCE TO LAW ENFORCEMENT, PROSECUTORIAL, JUDICIAL, OR CORRECTIONAL DECISIONMAKING. A STUDY OF DECISIONS AT EACH STEP IN THE JUVENILE AND CRIMINAL JUSTICE PROCESS COULD PROVIDE A USEFUL STARTING POINT FOR ASSESSMENT OF THE RATIONALITY OF THAT SYSTEM. A FOCUS ON DECISIONS MAY PROVIDE AT THE SAME TIME OPPORTUNITIES FOR INCREASING THE RATIONALITY, ESPECIALLY IF DEMONSTRABLY RELEVANT INFORMATION COULD BE PRESENTED TO DECISIONMAKERS TO ENABLE THEM TO ENHANCE THE PROBABILITIES OF ACHIEVING AGREED-UPON OBJECTIVES. AN ANALYSIS OF TYPICAL DECISION PROBLEMS ENCOUNTERED BY CRIMINAL JUSTICE DECISIONMAKERS EMPHASIZES THE NEEDS FOR IMPROVED DEFINITION AND MEASUREMENT OF OBJECTIVES, FOR MORE COMPLETE SPECIFICATION OF ALTERNATIVES, FOR EVIDENCE NOT NOW AVAILABLE ON THE CONSEQUENCES OF DIFFERING METHODS FOR HANDLING OFFENDERS OR PROVIDING TREATMENT FOR THEM, AND FOR BUILDING FURTHER ON PROGRESS MADE TOWARD USEFUL METHODS FOR CLASSIFYING OFFENDERS. A STUDY OF DECISIONS AIMED AT ASSESSMENT OF THEIR RATIONALITY SUGGESTS NEEDS FOR THE DEVELOPMENT OF INFORMATION SYSTEMS WHICH ARE EQUIPPED TO FOCUS ON PROGRAM EVALUATIONS AND TO PROVIDE ROUTINE FEEDBACK TO DECISIONMAKERS. SUCH SYSTEMS WILL HAVE TO TAKE ACCOUNT OF DECISIONMAKER STYLES IN ORDER TO BE EFFECTIVE. (RCB)