Joint ventures have been an important research topic over the last few decades primarily because of their importance as a strategic alternative in global competition. Due to the inherent complexities of international joint ventures (IJVs), involving a mixture of different managerial systems, attitudes, and business strategies, such entities are very difficult to manage. In this study, the effect of strategic, organizational, and cultural fit between IJV partners and of interpartner relations on IN performance is examined through a questionnaire survey. IJV performance is measured by means of two constructs: "project performance" and "performance of IJV management." The results point out the significance of the quality of partner relations for a successful IJV operation. Findings of the study also suggest that the level of organizational fit between the partners has a moderate influence on IJV performance. It was observed that strategic fit between IN partners affects interpartner relations extensively, which in turn affects IJV performance. IN partners with compatible technical and managerial skills, financial resources, organizational size, workload, and project experiences are expected to achieve greater IJV success.