The clinical features, radiographic and computed tomographic findings of nine patients with histological proof of cryptogenic organizing pneumonia were analysed. Patients present with cough, dyspnoea and malaise and commonly have bilateral multifocal consolidation on chest radiography, which may show resolution or relapse with or without steroid treatment. A good response to steroids is the rule, usually with complete radiological resolution or minimal residual scarring. The relative merits of the terms cryptogenic organizing pneumonia and bronchiolitis obliterans organizing pneumonia, both currently used to describe this entity, are discussed.