The essence of market orientation is the successful management of a relationship between suppliers and customers. During the past 15 years, a body of scholarship on antecedents and consequences of market orientation has emerged. But what is the appropiate level of market orientation, and what happend when the customers and the suppliers disagreeabout the appropiate level if a supplier's market orientation? To what extend does such agreement concerning market oruientation affect the customer-supplier relationship? Do answers to these questions vary by country? The authors examined the issues using data from a survey of leading Japanese and U.S. business firm and the key customers that employed a unique matched supplier-customer sampling methodology. The authors report several interesting results.