The historic triad of bronchial asthma, nasal polyposis, and intolerance to aspirin and related chemicals, recently designated as Samter's syndrome, is an inflammatory condition of unknown etiology and pathogenesis. The condition is probably acquired, perhaps secondary to a viral infection, but a hereditary factor may be important in some patients. Most patients with this syndrome are adults, with an occasional case being identified in a teenager or older child. Although not every patient will have the fully developed syndrome, the typical patient will have all three of the classic features. Many patients with Samter's syndrome also have a marked eosinophilia of both bronchial and nasal secretions as well as the circulating blood. Approximately 10 per cent of the patients have urticaria and/or angioedema, alone or in combination with respiratory inflammation. The diagnosis usually can be established easily on the basis of the history and physical examination, and only rarely in clinical practice is it necessary to perform a confirmatory aspirin challenge test. As with all allergic diseases, the cornerstone of treatment is environmental control with avoidance of respiratory irritants, aspirin, and aspirin-like medications. Management of upper airway disease requires careful prescription of medication supplemented by judicious selection of surgery. A variety of medications, including bronchodilators and corticosteroids, can be used to treat the bronchial symptoms. The results of current research are expected to lead to better understanding followed by further improvements in treatment for patients with Samter's syndrome.