Bioterrorism, the intentional release of biological pathogens, is distinct from other forms of terrorism in several important ways. Bioterrorist attacks are silent, low in cost and easy to replicate in multiple sites, and respect no geographical boundaries. With no central point of impact, explosion, or assault, the bioterrorist attack exists wherever and whenever one person transmits the infectious agent to another. But rather than recognizing the critical differences between nuclear, chemical, and biological attacks, analysts frequently group them into categories like "CBRN" (Chemical, Biological, Radiological, and Nuclear)—making it seem as if terrorist use of biological agents is merely another variant on a basic theme. This article details the differences that set bioterrorism apart, and discusses a number of implications for foreign policy decision makers, who ideally should be involved in planning for both the prevention and response to bioterrorism. Bioterrorism's distinctive foreign policy ramifications mean that those in the foreign policy establishment must work closely with public health leaders and others addressing national security to ensure effective strategies to address bioterrorism exist.