This study calculated the potential change in costs from regionalizing open heart surgery units in a geographic network of the Department of Veterans Affairs (VA). It used data from the VA's cost accounting system, and the authors conducted a sensitivity analysis. Under consolidation, savings from closing an open heart surgery unit would be partially offset by the costs of treating nonemergency cases at other VAs, treating emergency cases at non-VA hospitals, and transporting patients to regionalized facilities. Nevertheless, the potential savings from consolidation would exceed $3 million, or 18% of the network's costs of treating open heart surgery patients.