We present data on 10 patients with RA who developed glomerulonephritis which was not related to gold or penicillamine therapy. Although two of these patients had received gold this had been discontinued 13 and 18 yr before the diagnosis of glomerulonephritis. Seven patients presented with nephrotic syndrome and three with proteinuria and microscopic haematuria. Renal histology showed a membranous nephropathy (five patients), mesangial IgA nephropathy (two patients), focal segmental necrotizing glomerulonephritis (two patients) and focal segmental glomerulosclerosis (one patient).