The study, which was funded by the Department of Transportation, aimed at identifying cost-effective, antitheft performance criteria which can reduce the vehicle theft rate; at developing and testing an improved antitheft system that would comply with these criteria; and at recommending modifications to Federal Motor Vehicle Safety Standard 114, which specifies criteria for designers. Data on vehicle thefts were collected through a literature search and through interviews with experts. The results provide information on theft rates, motives, methods, and costs and serve as a basis for the performance criteria. Among these, time-to-defeat was found to be the basic attack resistance criterion, and 10 minutes was set as a goal. Others included limited accessibility to vulnerable components, an effective active or passive tamper-detection capability, and visual conspicuousness. The system designed included a remote steering lock with keyboard code insertion. In addition, interior baffles were added to the doorlock system, the interior release was modified to use a rotary knob, and a commercial hood lock was installed. The improved system resisted the efforts of a retired professional auto thief who gave up after 17 minutes. The ultimate consumer price is estimated to be between $17 and $36. A modification of the Federal standards to include a minimum time-to-defeat requirement is recommended. Data tables, diagrams, and photographs are included. For a related document, see NCJ 74476.