20 patients with rapidly progressive glomerulonephritis were treated at the nephrological section, Medical Department A, Haukeland Hospital from 1973 to 1988. Nine patients had an idiopathic type of nephritis, while seven patients had this type of glomerulonephritis secondary to systemic lupus erythematosus, endocapillary glomerulonephritis, Henoch-Schönleins purpura or Wegener's granulomatosis. Four patients had antibodies to glomerular basement membrane. All renal biopsies showed extracapillary proliferation and tubular cell damage. All patients were given immunosuppressive treatment with corticosteroids and cytotoxic drugs. Nine patients who were admitted to the hospital from 1973 to 1978 were not treated with plasmapheresis, 11 patients from 1978-1988 were all treated with plasmapheresis. After one year of observation, six of the nine patients in the first group had died, while this applied to only two in the group treated with plasmapheresis. Early diagnosis and plasma exchange, in addition to immunosuppression, seems to be the best treatment for these patients.