Lung transplantation appears to be one potential J approach to the management of such pulmonary diseases as severe emphysema. Present methods, however, do not permit adequate control of the rejection of homografts. In addition, the functional capacity of the autotransplanted lung is not completely understood. Pulmonary hypertension and a decrease in oxygen consumption have been described following reimplantation of the lung in dogs.1,2 Previous studies report rare survival of dogs with an autotransplanted lung following a contralateral pneumonectomy. Others have emphasized the serious loss of respiratory reflexes following total lung denervation.3 In contrast, Hardy and his associates4 state that although an autotransplanted lung may show impaired function early, there occurs "functional recovery of the reimplanted lung and probable regeneration of vagal nerve fibers to this organ." It is now well substantiated that surface forces are important in determining the mechanical behavior of the lung and that the