Sheep immunized with human lung and Freund's adjuvant develop progressive glomerulonephritis with deposition of autoantibodies and complement in the glomerular basement membrane. This nephritis appears to be the first autoimmune disease induced by antigens that are not organspecific. By clinical and immunopathologic criteria, this nephritis appears identical to the nephritis induced in sheep by human glomerular basement membrane and greatly resembles certain nephritides of man, in particular, the nephritis in Goodpasture's disease.