Vaccine-preventable diseases have historically caused much illness and death in South Dakota. Sixty-seven diphtheria deaths were reported in 1892 and 1,017 polio cases were reported at the peak of the polio epidemic in 1952. As vaccines have been developed, licensed and put into wide use, the rates of diphtheria, polio, measles, smallpox and other diseases have successfully decreased leading to control, statewide elimination or eradication. Other diseases, such as pertussis, have been more difficult to control by vaccination alone. Although current vaccination coverage rates for South Dakota's kindergarten children surpass the Healthy People 2020 targets of 95 percent, the coverage rates for 2-year-old children and teenagers are below the target rates. Until vaccine-preventable diseases are eradicated globally, we must vigilantly maintain high vaccination coverage rates and aggressively apply control measures to limit transmission when diseases do occur in South Dakota.