This paper notices the trust as social capital, and then attempts to investigate how it is treated in the discussion on the intellectual property management. Furthermore, this study makes clear enterprises' cognitions and approaches on trust, and then considers to a method of the management of trust based on the data obtained through a survey conducted with questionnaires on pharmaceutical enterprises in Japan. Trust as intellectual property resides in not particular individuals or organizations but such subjects as between an enterprise and their customers. The past framework on the concept of intellectual property doesn't capture the trust existed in among these subjects. This point may cause a limitation to the existing frameworks. As to enterprises' cognition on trust, almost all of enterprises reply to the same answers. But as to the approaches answer tendency are different. We can show a method of management of trust based on these results. (c) 2006 PICMET.