BEGINNING IN THE EARLY 19TH CENTURY IN THE UNITED STATES, INCREASED RELIANCE UPON COURTS EMERGED IN RESPONSE TO GROWING CONCERN FOR EFFECTIVE CRIME CONTROL. HOWEVER, IN THE MID-1960'S, EMPHASIS SHIFTED TO THE NEED FOR DEVELOPING OTHER RESPONSES TO CRIME, AND A PLETHORA OF DIVERSIONARY PROPOSALS AND PROGRAMS APPEARED, MANY FUNDED BY LEAA. AFTER EXTENSIVE COURT REFORM AND DIVERSIONARY PROGRAM DEVELOPMENT, THE LACK OF INSTITUTIONAL EFFECTIVENESS IN MODERATING CRIME STILL EXISTS. POLICIES SHOULD BE GROUNDED IN EMPIRICAL THEORY RATHER THAN IS COMMONLY HELD, BUT UNVERIFIED, BELIEFS. FOR POLICY TO IMPROVE, RESEARCHERS AND EVALUATORS MUST USE IMAGINATION, IMPROVE DATA, AND BE OPEN TO NEW CONCEPTIONS OF THE SYSTEM. TWO APPROACHES TO ACHIEVING LINKS AMONG DATA, THEORY, AND POLICY CAN BE IDENTIFIED: DOWNWARD POLICYMAKING AND UPWARD POLICYMAKING. IN DOWNWARD POLICYMAKING, PROBLEM AREAS ARE IDENTIFIED AND SYSTEMATICALLY INVESTIGATED; PRESSURE FOR CHANGE ORIGINATES CENTRALLY AND IS EVENTUALLY TRANSMITTED TO LOCAL AGENCIES. UPWARD POLICYMAKING FOLLOWS THE OPPOSITE PATTERN; IMPETUS FOR CHANGE COMES FROM THE LOCAL LEVEL, AND THE CHANGE PERCOLATES UPWARD AND OUTWARD. THE GOAL OF BOTH POLICY INVESTIGATIONS IS TO INCREASE THE KNOWLEDGE ON WHICH POLICY DECISIONS ARE BASED. OPERATIONAL PROBLEMS OF RESEARCHING THE CRIMINAL JUSTICE SYSTEM ARE EXPLORED IN TWO CHAPTERS DESCRIBING A MODEL OF DOWNWARD POLICYMAKING. ADDITIONAL CHAPTERS DESCRIBE LOCAL INNOVATIONS WITH EXISTING DATA, REPORT AN ANALYSIS OF LOCAL INNOVATION, AND EXAMINE SENTENCING PATTERNS OF JUDGES AND JURIES, THE ADJUDICATION OF MALE CODEFENDANTS, THE DECISION PROCESSES OF JURIES IN RAPE TRIALS, AND DIVERSION ISSUES. REFERENCES AND STATISTICAL TABULAR DATA ARE PROVIDED. (LWM)