Anaemia (haemoglobin 10.7 g/dl) and small spotty infiltrates in both lungs were found in an 18-year-old man who had increasing haemoptysis over the preceding 3 weeks. Bronchoscopy revealed diffuse bilateral pulmonary haemorrhage. Further diagnostic measures provided no evidence of involvement of other organs, in particular the kidneys. The demonstration of anti-basement membrane antibodies confirmed the diagnosis of a disease within the group of immune-induced alveolar haemorrhage. The radiological signs in the lungs regressed over 3 weeks of administering prednisone, initially 100 mg daily, then 60 mg daily, and the patient was discharged. While being treated as an out-patient, with reduction of prednisone to 10 mg daily, the haemoptysis recurred so that a single dose of cyclophosphamide, 1.5 g, was added to the immunosuppressive treatment. There was no further haemoptysis and the prednisone was discontinued after having been given for 15 months. The patient has now been in complete clinical remission for 3 years and anti-basement membrane antibodies are no longer demonstrable. At no time was there any evidence of renal involvement in the sense of the classical Goodpasture's syndrome.