The improvement in survival rate among patients with acute respiratory failure during the past 20 years is one of the major recent achievements in pulmonary medicine. As with most advances, however, there are some accompanying problems. The treatment of these patients with mechanical ventilation requires an artificial airway; in a few of the long-term survivors, recovery from respiratory failure is accompanied by the unfortunate development of stenosis of the upper (major or central) airways. The paper by Farmer et al in this issue of theArchieves(see p 309) reports on five such patients. In which patients should upper airway obstruction be suspected? Obviously, all dyspneic patients with a history of prolonged mechanical ventilation are likely candidates. However, it should be emphasized that a substantial proportion of patients with upper airway obstruction are not survivors of respiratory failure. The genesis of the obstruction in these cases is usually neoplastic. 1,2