Administration of recombinant erythropoietin constitutes a revolution in treatment of the anemia of chronic dialysis patients. Such treatment has been anxiously awaited. Its realization has been possible thanks to the spectacular progress allowed by the newly developed techniques of recombinant genetics. Correction of this type of anemia can be obtained rapidly and permanently if treatment is continued without interruption. It is followed by a remarkable transformation of the patient's physical and psychic status. The occurrence of certain side effects (e.g., elevation of blood pressure and an increased tendency toward vascular thrombosis), however, requires increased awareness in the follow-up of patients at risk and adaptation of erythropoietin administration to individual needs.