Cryptogenic fibrosing alveolitis (CFA) is a relatively uncommon condition with a variable prognosis and a mean survival of less than 5 years. The prediction of responsiveness to corticosteroid treatment is difficult, but is highly desirable because of the range of beneficial and harmful effects encountered with this treatment. This review of the clinical details of 42 patients with CFA managed at the Respiratory Clinic at Groote Schuur Hospital over the past decade highlights this difficulty, and draws attention to features which may be helpful in predicting response and prognosis. Although 53% of patients experienced symptomatic improvement or had an initial objective response to treatment, only 28% showed sustained improvement on lung function tests. The outcome and pattern of disease of patients in this study are very similar to those reported from other centres.