UNDER RECENT CALIFORNIA LEGISLATION, DRIVERS CONVICTED OF SUCH OFFENSES MAY PARTICIPATE IN A 12-MONTH ALCOHOL ABUSE TREATMENT PROGRAM INSTEAD OF RECEIVING MANDATORY LICENSE SUSPENSION OR REVOCATION. BOTH CLOSE SUPERVISION AND TREATMENT SERVICES ARE INCLUDED. THE EVALUATION GOALS WERE TO ASSESS IMPACTS ON TRAFFIC SAFETY AND DRIVER LIFESTYLE AND TO MAKE RECOMMENDATIONS FOR A FIRST OFFENDER PROGRAM AND FOR FUTURE PROGRAM AND EVALUATION NEEDS. A QUASIEXPERIMENTAL EVALUATION DESIGN WAS USED TO COMPARE DATA FROM FOUR COUNTIES WHICH IMPLEMENTED THE PROGRAM AND FOUR NONPARTICIPATING COUNTIES. TREATMENT PARTICIPANTS WERE COMPARED BOTH WITH NONPARTICIPANTS IN THEIR COUNTIES AND WITH OFFENDERS FROM THE COMPANION COUNTIES. PROGRAM PARTICIPANTS HAD THE WORST SUBSEQUENT ACCIDENT AND CONVICTION RECORDS, UNDOUBTEDLY DUE TO HIGHER DRIVING EXPOSURE. LIFESTYLE IMPROVEMENTS OCCURRED IN BOTH THE TREATMENT AND THE LICENSING ACTION GROUPS. THE TREATMENT PROGRAM DEMONSTRATED NO ADVANTAGE OVER MANDATORY LICENSING CONTROLS DURING THE TREATMENT PERIOD. NEVERTHELESS, THE PROGRAM PRODUCED SOME OPERATIONAL BENEFITS. IT IS RECOMMENDED THAT THE METHOD OF SELECTING DRIVERS FOR TREATMENT BE REFINED, PROGRAM EFFECTIVENESS BE FURTHER EVALUATED, AND FOLLOWUP EVALUATION BE CONDUCTED. FIRST OFFENDERS SHOULD BE EXCLUDED FROM THE PROGRAM, SIMULTANEOUS IMPOSITION OF LICENSING ACTION AND PROGRAM PARTICIPATION SHOULD BE CONSIDERED, AND RANDOM ASSIGNMENT SHOULD BE PERMITTED TO AID EVALUATION. FINALLY, MULTIPLE OFFENDERS SHOULD BE ASSESSED A FEE EQUAL TO THE COST OF IMPOSING THE MANDATED LICENSING ACTION. RESULTS CANNOT BE GENERALIZED TO FIRST OFFENDERS. METHODS OF DETECTING FIRST OFFENDERS SHOULD BE EXPLORED AND STRINGENT COUNTERMEASURES ESTABLISHED. TABLES, FOOTNOTES, A REFERENCE LIST, AND APPENDIXES PRESENTING RELEVANT LEGISLATION AND ADDITIONAL DATA RELATED TO THE EVALUATION, ARE INCLUDED. (CFW)