A review is presented of antiglomerular basal membrane antibody-mediated glomerulonephritis (anti-GBM-Ab-nephritis) which constitutes 2-5% of all cases of acute glomerulonephritis. The disease frequently commences in the age group 20-30 years but may be encountered in all age groups, in women particularly at 60 years of age. The disease is due to autoantibodies (IgG) to the basal membranes in the glomeruli and alveoli. Deposition of IgG with C3 precipitates an inflammatory reaction which causes renal and possibly also pulmonary damage. It is possible to demonstrate anti-GMB-antibodies in the blood and, by means of immunofluorescence microscopy, these and C3 may be demonstrated in the basal membranes in the glomeruli and alveoli. The disease is still serious but introduction of immune-suppressive treatment and plasmapheresis has improved the prognosis considerably.