The causes of death in 84 end-stage renal failure patients, treated with dialysis, who died during a 66-month period were reviewed retrospectively. Cardiac and infectious diseases were the main cause of death (27% each). These two constituted 44% of causes of death in hemodialysis and 75% in continuous ambulatory peritoneal dialysis patients. Malignant disease (7%) and hyperkalemia (5%) were responsible for death only in hemodialysis patients. Patients who died following hyperkalemia were younger than 50 years old. Patients who died from malignant disease were dialyzed for more than 3 years. In summary, the mode of dialysis therapy, age at start of therapy, time on dialysis, and previous cardiac disease may play a role in determining the causes of death in dialysis patients.