IT IS WRITTEN MORE AS A THREE-PART ESSAY OFFERING GUIDELINES TO EVALUATION THAN AS A DETAILED, STEP-BY-STEP METHODOLOGY. THE FIRST SECTION SUMMARIZES THE MODEL OF TRADITIONAL PREVENTIVE PATROL DEVELOPED IN ANOTHER VOLUME IN THIS REPORT SERIES, 'TRADITIONAL PREVENTIVE PATROL: AN ANALYTICAL FRAMEWORK AND JUDGMENTAL ASSESSMENT (NCJ-35449), AND UPON WHICH THIS EVALUATION DESIGN IS BASED. THE SECOND SECTION DESCRIBES AN APPROACH FOR EVALUATING PATROL OPERATIONS WHICH CALLS FOR A DETAILED EXAMINATION OF THE ENTIRE PATROL SYSTEM AND ALLOWS FOR THE USE OF CRITICAL JUDGMENTS WHICH ARE BASED UPON THE EXPERIENCE AND AVAILABLE DATA WITHIN INDIVIDUAL DEPARTMENTS. THE THIRD SECTION OF THIS ESSAY DISCUSSES BRIEFLY THE BENEFITS TO BE OBTAINED FROM APPLYING THIS FIRST ORDER EVALUATION DESIGN. ATTACHED EXHIBITS COVER A MODEL OF PATROL, A FLOW DIAGRAM FOR SITE-SPECIFIC EVALUATION DESIGN, PREVAILING TACTICAL AND STRATEGIC ASSUMPTIONS AND A UNIVERSE OF ASSUMPTIONS GOVERNING DEPLOYMENT, SUPERVISION, IN-SERVICE TASK ASSIGNMENTS, AND PATROL MODES. ALSO INCLUDED IS A UNIVERSE OF ASSUMPTIONS RELATING TO OFFICER CHARACTERISTICS. FOR OTHER RELATED DOCUMENTS IN THIS SERIES, SEE NCJ-35439 AND 35449 AND 48. (AUTHOR ABSTRACT MODIFIED)