The federal End State Renal Disease (ESRD) program was created by statute in 1972 as a general population entitlement to be administered by Medicare. The program extends all Medicare benefits to patients, regardless of age, who are diagnosed as having ESRD, as long as they are fully insured for old age and survivor insurance benefits (Social Security), are entitled to monthly insurance benefits under the Social Security Act, or are spouses or dependent children of individuals with the foregoing Social Security benefits. About 7 percent of all ESRD patients are excluded from this entitlement by these criteria. The two major therapies embraced by the ESRD program are renal dialysis and kidney transplantation. In this first part of a two-part article, dialysis is the focal point. Kidney transplants will be covered in the May-June issue of Physician Executive.