A hemodialysis device with a surface of 5 m2, a blood flow (QB) of 500 ml/min, and a dialysate flow (QD) of 1,000 ml/min has enabled the authors to obtain in 6 h/week the same clearances for urea, creatinine, uric acid, phosphates, and vitamin B12 as has conventional hemodialysis (CH), which takes from 12 to 15 h/week. Twenty-five patients were hemodialyzed throughout 1 year with CH and another year with large-surface hemodialysis, 20 with a creatinine clearance (CCr) of 0.5 ml/min and 5 with a CCr between 0.5 and 4.5 ml/min. All followed a free diet and led a normal life. Hemodialysis time was 6 h/week, and the results obtained were equal to those of the previous year with a CH of 12 h/week. The use of a bicarbonate dialysate rich in glucose, with a relatively high level of potassium and sodium, can avoid the disequilibrium syndrome caused by quick hemodialysis and makes possible the removal of excess liquid in only 6 h/week, without disturbances for the patient.