ALTHOUGH THE 16 HIGHWAY SAFETY PROGRAM STANDARDS HAVE BEEN IN EFFECT FOR SOME TIME, THEIR ADOPTION BY THE INDIVIDUAL STATES HAS BEEN LESS THAN COMPLETE. TO CONVINCE THE LOCAL GOVERNMENTS THAT THE REQUIREMENTS IMPOSED BY THESE STANDARDS ARE WELL WORTH THEIR COST IN IMPROVED SAFETY BENEFITS, A NEED EXISTS FOR DETERMINING AND RANKING THE EFFICACY OF HIGHWAY SAFETY COUNTERMEASURES. THE RESULTS OF A ONE-YEAR STUDY TO DETERMINE A PROGRAM PLANNING METHODOLOGY FOR THE EVALUATION OF HIGHWAY SAFETY COUNTERMEASURES ARE COVERED. PROGRAM PLANS FOR EACH OF THE SIX EVALUATION EXPERIMENTS ARE PRESENTED. EXPERIMENTS INCLUDE: (1) ROAD USER REGULATION; (2) INFORMATION FLOW; (3) ROAD USER PREPARATION; (4) VEHICLE REGULATION; (5) SYSTEM RESTORATION; AND (6) HIGHWAY REGULATION. /HSRI/