The Natìonal Highway Traffic Safety Administration’s vehicle aggressivity and compatibility research program explores the global evaluation of vehicle crashworthiness designs as a means of minimizing injuries in the design Vehicle While simultaneously minimizing injuries in the vehicle’s collision partners. The program pursues both an analytic investigation of fleet Wide Vehicle performance as the basis for global optimization and pursues an experimental component as the foundation for validation of computer models and tools. This paper presents an overview of this research program along with a summary of the results achieved to date.