The authors describe massive, fatal alveolar hemorrhage in an 82-year-old woman in whom a diagnosis of Wegener's granulomatosis was made at postmortem examination. A literature review revealed a total of 18 case reports of this entity that were described in sufficient detail to permit abstraction of clinical characteristics. When compared with a large series of patients with more "typical" Wegener's granulomatosis, patients with alveolar hemorrhage had more evidence of systemic vasculitis and glomerulitis and less evidence of upper airway disease. Alveolar hemorrhage was associated with greater than 50% mortality, reflecting in part, the fulminant nature of this complication of Wegener's granulomatosis. All survivors had been treated with cytotoxic agents; those who died had either no specific therapy or were treated either with corticosteroids alone or died before cytotoxic therapy could be expected to be effective. Wegener's granulomatosis should be in the differential diagnosis for patients who present with alveolar hemorrhage with or without renal failure. An aggressive diagnostic approach and the earliest possible administration of cytotoxic drugs in combination with corticosteroids offer the best chance of survival in this fulminant condition.