The Marseille public hospital system (APHM) has expressed its willingness to pool its services of immunohematology and delivery of labile blood products with those of the French blood institute Alps Mediterranean division (EFS AM). An agreement setting out the terms of this partnership was signed between the two parties. The users of the APHM and EFS AM blood watch wished to preserve the channels of distribution. Implementation of this reorganization has focused on ensuring transfusional safety, reinforcing harmonization of APHM practices, and finding ways to reduce costs. Despite joint information campaigns (to medical and paramedical personnel) carried out by the APHM and EFS AM blood watch, problems have arisen during start-up and adjustments have been necessary on both sides. The success of this project hinges on the involvement of the EFS AM in our transfusional practices, deployment of a system for diffusion of information, and consolidation of physical and human resources at the level of the APHM blood watch. (C) 2009 Elsevier Masson SAS. All rights reserved.