The study is intended to explore determinants of joint action in automobile distributor-supplier relationships. It provides more research in behavioral exchange and, in addition to economizing motives, includes strategizing motives to explore their impacts on the joint action. From the economizing motives perspective, the distributor dependence increases as the distributor motivational investment and specialized investment increase. As a distributor depends more on its supplier, the joint action will increase; therefore its performance will be better improved. From the strategizing motives perspective, the distributor service differentiation increases as the distributor specialized investment and competitive intensity increase. As a distributor provides more differentiate services to customers, the joint action will increase; therefore its performance will be better improved.