Through the global research of the past decade, it can be said that fundamental issues of frontal impact compatibility have been almost fully understood. The first step is to enhance the structural interaction between the front-end structures of colliding vehicles and the next step is to help match the stiffnesses between vehicles. In the previous ESV conference, the authors reported the results of a study in which stiffness matching in SUV-to-car frontal impact was accomplished by increasing the car's stiffness only[9]. In this paper, the stiffness matching in SUV-to-car frontal impact will be accomplished by only reducing the SUV’s stiffness using FE (finite element) vehicle models. These two studies would contribute to furthering the research for more practical compatibility countermeasures.