It is commonly assumed that with declining adult mortality rates, the elderly population will continue to increase and become a major fiscal problem for the Medicare program. However, this population, like other age groups, consists of a small number of frequent medical-care users and a large number of low-frequency users. If the decline in mortality rates occurs as a result of primary and secondary prevention efforts rather than tertiary interventions, a 26.4 percent increase in the population 65 years of age and older could result in only a 19.4 percent increase in gross Medicare expenditures and a slight decline in net Medicare expenditures.