Along with smallpox, inhalation anthrax and pneumonic plague are among the diseases most likely to be spread by biowarfare, either from a rogue nation or terrorist group. Neither anthrax nor plague has been seen by many pulmonary (or any other) physicians in the United States. This article summarizes these two diseases as pulmonary manifestations of bioterrorism and discusses the possibility of avian influenza as a potential respiratory pathogen in biowarfare. It is hoped that phyisicians will need to know this information only as an academic exercise and not because of a clinical circumstance.