The health and life expectancy of persons residing in the United States has improved dramatically during the 20th century. The average life span in the US has increased by more than 30 years since 1900. This significant gain is attributable to improvements in both public health and medical care. Tempering this notable achievement is the observation that the mortality rate per 1,000 population, although showing a significant decline in the era from 1920 to 1940, has now plateaued, and may be showing a slight increase. Our scientists and physicians have appropriately exploited the scientific discoveries of the 20th century and are poised as a medical tour de force for the 21st century. The decline in deaths from coronary artery disease and stroke has resulted from risk-factor modification and the innovations of surgeons and physicians who have dedicated themselves to early detection and better treatment of these cases. During the 1960s, patients admitted to our medical center with advanced Hodgkin's disease, hairy cell leukemia, and the acute leukemias had a life expectancy of < 1 year. Today, even advanced Hodgkin's disease and hairy cell leukemia are curable, and many patients with other acute leukemias respond to therapy and have very durable remissions. The rate of maternal mortality has shown a dramatic decline, and many childhood diseases have been eradicated or reduced to infrequent occurrences. Our public health scientists and physicians are joining forces to further diminish the morbidity and mortality rates for many of our common diseases. The achievements of our past afford us the vision for what we can become.