Since the declaration of the eradication of smallpox in May of 1980 concern about this virus has ebbed. However, recent world events, including the destabilization of governments, have raised concerns that smallpox could fall into the hands of nefarious individuals or groups who might attempt to use the virus as a weapon. In Centers for Disease Control and Prevention publications the threat of smallpox being intentionally released by bio-terrorists is currently considered possible. Because health educators would likely be involved in public health prevention and response efforts to a release, it is our responsibility to be knowledgeable about smallpox. This article defines the disease, describes its history and the successful eradication effort, and discusses public health preparations for the possible return of this killer.