THE ANTIHIJACKING PROJECT WAS SPONSORED BY THE NATIONAL INSTITUTE OF LAW ENFORCEMENT AND CRIMINAL JUSTICE. THE INITIAL PHASES OF THE PROJECT IDENTIFIED THE MOST VULNERABLE POINTS OF CARGO SHIPPING AND DEMONSTRATED THE FEASIBILITY OF AN AUTOMATIC VEHICLE MONITORING SYSTEM BASED ON AM (AMPLITUDE MODULATION) BROADCAST SIGNALS. THIS FIELD TEST INVOLVED 40 TRUCK ROUTES BELONGING TO 2 COMMERCIAL TRUCKING COMPANIES IN THE LOS ANGELES, CALIF., AREA WITH CONTROL DATA SUPPLIED BY 2 ADDITIONAL COOPERATING FIRMS. TOTAL ROUTE-MILES FOR BOTH TEST AND CONTROL GROUPS WERE ABOUT 400 SQUARE MILES. THIS REPORT DESCRIBES THE FIELD TRIAL METHODOLOGY AND GIVES A NONTECHNICAL DESCRIPTION OF THE AUTOMATIC TRUCK MONITORING SYSTEM. DURING THE EARLY PHASES OF THE TEST THE SYSTEM ENCOUNTERED COMMUNICATIONS INTERFERENCE WITH OTHER LOCAL USERS, RESULTING IN A DECISION TO CEASE TESTING. HOWEVER, THE FIELD TRIAL DID PROVE THE FEASIBILITY OF A WIDE-AREA MONITORING SYSTEM CAPABLE OF BEING SHARED BY MULTIPLE USERS WITHOUT COMPROMISE OF INDIVIDUAL DATA INTEGRITY. DESIGN MODIFICATIONS TO ELIMINATE THE INTERFERENCE PROBLEM ARE IDENTIFIED. FURTHER TESTING IS URGED. AN APPENDIX CONTAINS DOCUMENTATION AND A LIST OF HARDWARE PRODUCED FOR THE PROJECT.