The majority of trauma patients (>90%) do not require any blood product transfusion and their mortality is <1%. However, 3% to 5% of civilian trauma patients will receive a massive transfusion (MT), defined as >10 units of packed red blood cells (PRBC) in 24 hours. In addition, more than 25% of these patients will arrive to emergency departments with evidence of trauma-associated coagulopathy. With this combination of massive blood loss and coagulopathy, it has become increasingly more common to transfuse early the trauma patients and with a combination of PRBC, plasma, and platelets. Given the inherent uncertainties common early in the care of patients with severe injuries, the efficient administration of massive amounts of PRBC and clotting factors tends to work best in a predefined, protocol driven system. Our purpose here is to (1) define the problem of massive hemorrhage and coagulopathy in the trauma patient, (2) identify which group of patients this type of protocol should be applied, (3) describe the extensive coordination required to implement this multispecialty MT protocol, (4) explain in detail how the MT was developed and implemented, and (5) emphasize the need for a robust performance improvement or quality improvement process to monitor the implementation of such a protocol and to help identify problems and deliver feedback in a "real-time" fashion. The successful implementation of such a complex process can only be accomplished in a multispecialty setting. Input and representation from departments of Trauma, Critical Care, Anesthesiology, Transfusion Medicine, and Emergency Medicine are necessary to successfully formulate (and implement) such a protocol. Once a protocol has been agreed upon, education of the entire nursing and physician staff is equally essential to the success of this effort. Once implemented, this process may lead to improved clinical outcomes and decreased overall blood utilization with extremely small wastage of vital blood products.