IN 1973, NEW YORK STATE ENACTED A COMPREHENSIVE SET OF 'GET TOUGH' DRUG LAWS WHICH INCREASED THE SEVERITY OF PENALTIES FOR DRUG OFFENSES, RESTRICTED PROSECUTORIAL DISCRETION TO PLEA BARGAIN, AND LIMITED JUDICIAL DISCRETION TO IMPOSE SENTENCES THAT DID NOT INVOLVE INCARCERATION. THE EVALUATION PROJECT SYSTEMATICALLY COLLECTED LARGE QUANTITIES OF DATA, CONDUCTED INTERVIEWS WITH KNOWLEDGEABLE PERSONS, CARRIED OUT EXTENSIVE STATISTICAL ANALYSES, AND CONSULTED SCHOLARS WITH RELEVANT EXPERIENCE. OVERALL, THIS EVALUATION INDICATES THAT, DURING THE FIRST 3 YEARS AFTER THEIR PASSAGE, THE OBJECTIVES OF THESE LAWS TO CONTROL ILLEGAL DRUG USE AND RELATED CRIME WERE NOT ACHIEVED. FOR EXAMPLE, HEROIN USE WAS AS WIDESPREAD IN NEW YORK CITY IN MID-1976 AS IN 1973, AND PATTERNS OF ILLEGAL DRUG USE OVER THIS PERIOD WERE NOT APPRECIABLY DIFFERENT FROM THOSE IN OTHER MAJOR EAST COAST CITIES. THE STATE'S PATTERNS OF DRUG-RELATED PROPERTY CRIMES WERE SIMILAR TO THOSE IN NEARBY STATES, AND ITS STIFF PENALTIES FOR REPEAT OFFENDERS PRODUCED NO SUSTAINED DETERRENT EFFECTS. FINALLY, ALTHOUGH INITIAL INCREASES IN COURT CASELOAD BACKLOGS AND OTHER IMPACTS ON THE CRIMINAL JUSTICE SYSTEM TENDED TO LEVEL OFF, THE COSTS IMPOSED BY THESE LAWS DID NOT APPEAR TO HAVE YIELDED COMMENSURATE BENEFITS. THE STUDY'S REPORT DESCRIBES THE PROBLEMS OF THE LAWS' IMPLEMENTATION, DETAILS RESEARCH METHODS AND FINDINGS, AND PROVIDES SUPPLEMENTAL MATERIALS FROM STAFF TECHNICAL ANALYSES OF MAJOR EVALUATION ISSUES. AN APPENDIX PROVIDES THE PRINCIPAL PROVISIONS OF THE 1973 NEW YORK STATE DRUG LAW. (AUTHOR ABSTRACT MODIFIED)