The aim of the present report was to compare the current patterns of incidence and prevalence of end-stage renal failure and mode of renal replacement therapy in patients with Type 1 (insulin-dependent) and Type 2 (non-insulin-dependent) diabetes mellitus in Europe. All Type 1 and Type 2 diabetic patients recorded on the Registry of the European Dialysis and Transplant Association as being alive on renal replacement therapy were analysed according to age, sex, geographic distribution, and mode of therapy (haemodialysis, peritoneal dialysis or renal transplantation). During 1990 3981 diabetic patients commenced renal replacement therapy in Europe, and at 31 December 1990 a total of 15,197 diabetic patients were receiving treatment. One-third were reported to be Type 2 diabetic patients, but the true proportion is expected to be higher. Both male and female Type 2 diabetic patients were older than Type 1 patients. Major geographic variations were observed; annual acceptance of Type 2 diabetic patients for treatment was greatest in Austria (10.7 per million) and equal to Type 1 patients, whereas the number of Type 1 diabetic patients was four times that of Type 2 patients in Sweden, Finland and Norway. Overall, the majority of Type 2 diabetic patients (80%) were treated by haemodialysis, 14% by peritoneal dialysis, and 6% had a functioning renal transplant. However, transplantation was the preferred option in young patients (48% of 25-34 year olds) and in Sweden and Norway (45% of all Type 2 patients).