自從政府開辦全民健保，以及開放國外醫藥產品之進口後，國內製藥業者面臨著空前未有的挑戰。從行銷通路挑戰之觀點來看，製藥業者首須面對的是國內三類機構買者之壓力，包括醫院、診所及藥局。在競爭激烈的市場中，誰能掌握通路，將決定誰是市場的贏家。這對醫藥市場而言亦是千真萬確的；因此，製藥業者重新思考及定位其與機構買者間之關係，確實是一個頗具意義，並且是相當重要的一個課題。 本研究旨在從機構買者之觀點探討醫藥市場第一層通路之組織間關係的問題，在理論架構的建立方面，本研究主要依據目前研究組織間關係的二大主流理論－交易成本理論與代理理論，建立一個「製藥業者－機構買者」之組織間關係管理的觀念性研究架構。首先，從交易成本與代理理論之相關文獻，本研究彙整歸納出資訊不對稱、投機主義、目標不一致、風險認知差距等，作為製藥業者與機構買者在互動過程中所衍生出來的交易成本與代理成本之主要因素。其次，本研究亦根據通路管理之相關文獻，彙整出信任、承諾、正式控制機制、組織間協調，以及衝突之化解等組織間關係的行為規範；這些行為規範有助於交易成本與代理成本之降低，故對「製藥業者－機構買者」之組織間互動關係的績效應有正面之影響。 在實証研究方面，本研究採問卷調查方式，以國內醫院、診所及藥房為研究對象。本研究實証結果顯示，交易成本理論與代理理論確實可解釋國內製藥業者與機構買者間之互動關係。此一實證結果除了有其組織理論應用在行銷通路研究之學術意涵外，對於實務界之運作亦提供了管理意涵。

Recently, the pharmaceutic industry's distributional channel is changing rapidly. The mainly factors such as pharmaceutic regulations changed. The foreignal pharmaceutic firms, and the pharmaceutic technology changed, and so on. Under these challenge, the domestic pharmaceutic firm had to think their interorganizational relationships (IORs) with institutional buyer-Hospital, General Practioner, and Drugstore. How to leverage the interorganizational relationship had become the most important topic. About this topic, few literature try to answer a series of questions including the determinants of IORs. The cost/benefit of managing IORs, and the performance. This study want to explore the nature of IORs between pharmaceutic manufactures and institutional buyers. Baed on transaction cost theory and agency theory, we develop an conceptual framework, which composed of the transaction cost and agency cost. The interorganizational behavioral norms and the institutional buyer's performance. Refer to the empirical study, we want to design questionnaires and send to the institutional buyer. Next, through the multivariate statistic methods, we will propose some meaningful conclusion. And finally, we also draw some suggestions and implications for the academic research and pharmaceutic firms.