Biological warfare is defined as the deliberate use of microorganisms or toxins derived from living organisms to induce death or disease in humans, animals or plants. Until recently the U.S. has been rather complacent about the bioterrorism threat. It is quite likely that terrorist use of weapons of mass destruction against the United States will become a true reality. Targets such as livestock, crops, tourism and transportation are likely terrorist choices in the future. Even small outbreaks of exotic disease in livestock or crops could remove the U.S. from the world market which it enjoys for its agricultural products. Critical to response in the event of a biological attack is the rapid identification of the etiologic agent or agents. The causative agent may be microbes and toxins that are not normally encountered in conventional labs. This may make the process of their identification slower and more difficult because of the requirements for reagents, equipment and specially trained personnel. Nevertheless, a rapid and reliable identification would be necessary in view of the critical management decisions that must follow. Numerous measures can be taken to reduce the human and economic impact.