It has been reported that the use of key phrases that all staff share a common understanding of is effective for integration inside an organization. At the Rakuwakai Otowa Hospital, however, integration failed due to the long-standing use of the terms “for the patient” and “patient first.” The staff had assigned different meanings depending on their profession to these terms based on which they had built successful track records for their profession. That experience acted as an inertia preventing changes in attitudes and behaviors and ended up accelerating individually optimal activities for each profession. It is not merely a matter of staff across units simply using the same key phrases; it is important to reduce the ambiguity of the key phrases through behavior.