Protein-energy malnutrition (PEM) is a common complication in maintenance hemodialysis and chronic peritoneal dialysis patients and is a powerful predictor of morbidity and mortality. Although this association does not prove that malnutrition is a cause of this increased morbidity and mortality, it is consistent with this possibility. There are a number of modalities of nutritional support for the prevention or treatment of PEM in maintenance dialysis patients. Routine methods include preventing PEM before the onset of maintenance dialysis therapy, dietary counseling, maintenance of an adequate dose of dialysis, avoidance of acidemia, and aggressive treatment of superimposed catabolic illness. Specific treatments of chronic dialysis patients who have persistently inadequate nutritional intake include food supplements, enteral tube feeding, intradialytic parenteral nutrition, and total parenteral nutrition. More experimental forms of nutritional therapy include dialytic nutrition (eg, using peritoneal dialysate or hemodialysate that contains amino acids), appetite stimulants (eg, megestrol acetate), or growth factors (eg, anabolic steroids, recombinant human growth hormone, or insulin-like growth factor-1). (C) 1999 by the National Kidney Foundation, Inc.