THE NATURE AND PURPOSE OF PSYCHOPHYSICAL EVALUATION IN DWI CASES ARE DISCUSSED, AND THREE CATEGORIES OF PSYCHOPHYSICAL TESTS ARE DIFFERENTIATED. TESTS IN THE INITIAL EVALUATION CATEGORY ARE BASED ON THE OFFICER'S ASSESSMENT OF THE DRIVER'S GENERAL PHYSICAL APPEARANCE AND CONDITION WHILE THE DRIVER IS STILL SEATED IN THE VEHICLE. TESTS IN THE NONSTRUCTURED EVALUATION CATEGORY INVOLVE ASSESSMENT OF THE DRIVER'S BASIC MENTAL AND PHYSICAL CONDITION INCLUDING BODY COORDINATION, JUDGMENT, BALANCE, MENTAL AWARENESS, ETC. TESTS OF THE THIRD TYPE ARE MORE STRUCTURED AND INCLUDE MENTAL AND PHYSICAL EXERCISES DESIGNED TO EVALUATE COORDINATION, EQUILIBRIUM, JUDGMENT, COMPREHENSION, AND CONCENTRATION. GUIDELINES FOR CONDUCTING SPECIFIC TESTS WITHIN EACH CATEGORY ARE PRESENTED, AS ARE INSTRUCTIONS FOR USING ALCOHOLIC INFLUENCE REPORT FORMS IN DWI CASES. THE NATURE AND PURPOSE OF CHEMICAL TESTING IN DWI ENFORCEMENT ARE DISCUSSED, AND INFORMATION ON SPECIFIC TESTS--BREATH, BLOOD, URINE--IS PRESENTED. THE ARRESTING OFFICER'S LEGAL RESPONSIBILITIES RELATIVE TO CHEMICAL TESTING IN DWI CASES ARE OUTLINED. APPENDED MATERIALS INCLUDE COPIES OF ALCOHOLIC INFLUENCE REPORT FORMS DEVELOPED BY THE NATIONAL SAFETY COUNCIL AND BY THE STATE OF MARYLAND AND DETAILS OF MARYLAND STATE POLICE PROCEDURES FOR SUBMITTING BLOOD AND URINE SAMPLES IN DWI CASES. MULTIPLE-CHOICE QUESTIONS ARE INCLUDED AS A STUDY AID. (LKM)