本研究探討汽車經銷商與供應商之間的聯合行動，不僅增加關係交易中行為因素的研究，並在經濟動機的考量之外，探究策略動機對聯合行動的影響。結果發現，從經濟動機而言，經銷商的動機性投資與特殊資產愈多，對供應商的依存度也愈高，使得經銷商願意配合供應商，共同採取聯合行動，進而提升經銷商的績效；從策略動機而言，經銷商投入的特殊資產越多，市場的競爭強度越激烈，則經銷商會提供給顧客更多差異化的服務，然而為了服務差異化，以獲取競爭優勢，就會與供應商採取聯合行動，進而提昇經營績效。

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 persepctive, 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 increase 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.