Two kidneys were removed from a cadaveric donor with 17-year history of type 1 diabetes. At the time of death the donor had proteinuria but normal serum creatinine, and on histological examination the kidneys showed features of established diabetic nephropathy including diffuse glomerulosclerosis and thickening of mesangial matrix and capillary basement membranes. After transplantation into non-diabetic recipients (cold ischaemia times 46 h and 52 h) the kidneys functioned well with standard immunosuppression. Renal biopsy specimens taken 7 months after transplantation showed almost complete resolution of the nephropathy and both patients remain free from proteinuria after a further 7 months. As well as indicating that longstanding type 1 diabetes need not always contraindicate kidney donation, these observations are relevant to the pathogenesis and management of diabetic nephropathy.