The kidney functions as an excretory, regulatory, and endocrine organ. The healthy kidneys: 1) excrete metabolic end-products as well as excrete and selectively reabsorb eledtroytes; (2) regulate water, acid-base balance, and systemic blood pressure; and 3) produce erythopoietin, which is responsible for the regulation of red cell production in the bone marrow, and activate vitamin D to its biologically active form-both endocrine actions. Chronic kidney diseases involve a gradual destruction of the functional kidney units or nephrons. The remaining healthy nephrons compensate, but with the continuing loss of nephrons, eventually the disease overwhelms the adaptive mechanisms. The result is a breakdown in the excretory, regulatory, and endocrine functions of the kidneys, leading to accumulation of protein waste products, sodium, potassium, phosphate, and water. As diet is the only source of most of these substances, dietary treatment becomes an integral part of management in the chronic renal failure patient. The treatment can be successful only when the relationship of the diet to the disease and knows how to plan daily meals to meet the dietary prescription.