Medical insurance that is a nationwide health insurance program for persons age 65 years and older and certain disabled or blind individuals regardless of income, administered by the Centers for Medicare and Medicaid Services (CMS), formerly HCFA. It was established by §1831 of the Title XVIII of the Social Security Act of 1965. Local Social Security offices take applications and supply information about the program. Benefits include physicians’ services, outpatient hospital care, durable medical equipment, and some medical services that are not covered by Part A. Physicians transmit their insurance claims to fiscal agents/intermediaries for payment. Ten regional offices provide CMS with a decentralized administration and delivery of Medicare programs. Each regional office oversees private insurance companies that contract with the government to process and pay for Medicare Part B benefits. Also referred to as supplementary medical insurance (SMI) .