A strategic Emergency Department alliance between a medical center, a regional hospital and a community hospital in Taoyuan county ren from July 1, 1998 to June 30, 1999, and was supported by the Department of Health. This paper focuses on the process of formatting, communicating and implementing the plan while the three emergency departments developed the alliance. The plan was executed smoothly in terms of medical staffing, corporate identity systems, duty rules, education, risk sharing, and patient transfer rules. Problems in consultation and manpower support across departments persisted despite discussion and trials. This report describes how the willingness and management abilities of those in charge, as well as identification of key participants strongly influenced the success of the emergency department strategic alliance.