Oxygen, PEEP, and mechanical ventilatory therapy should be administered to patients in varying amounts and should be removed gradually and independently. The method of determining optimal PEEP, oxygen, and ventilation is not unlike that recommended for many other therapies. Nine years of prospective evaluation have demonstrated the numerous clinical advantages of this technique, and relatively few complications have been associated with it. Reduced FIO2 may promote resistance to atelectasis and allow rapid discontinuation of mechanical ventilation and PEEP. Similarly, optimal levels of PEEP may improve matching of ventilation and perfusion and assist lung mechanics so that FIO2 and mechanical ventilation may be reduced. Minimal mechanical ventilatory support eliminates iatrogenic respiratory alkalosis, and weaning from ventilatory support may be initiated early. This, in turn, minimizes the detrimental effects of mechanical ventilation on acid-base balance and cardiovascular function, as well as lessening barotrauma. We think that this approach has simplified the clinical management of patients with compromised repiratory function and decreased their mortality.