▪ Abstract Biological weapons are not new. Biological agents have been used as instruments of warfare and terror for thousands of years to produce fear and harm in humans, animals, and plants. Because they are invisible, silent, odorless, and tasteless, biological agents may be used as an ultimate weapon—easy to disperse and inexpensive to produce. Individuals in a laboratory or research environment can be protected against potentially hazardous biological agents by using engineering controls, good laboratory and microbiological techniques, personal protective equipment, decontamination procedures, and common sense. In the field or during a response to an incident, only personal protective measures, equipment, and decontamination procedures may be available. In either scenario, an immediate evaluation of the situation is foremost, applying risk management procedures to control the risks affecting health, safety, and the environment. The microbiologist and biological safety professional can provide a practical assessment of the biological weapons incident to responsible officials in order to help address microbiological and safety issues, minimize fear and concerns of those responding to the incident, and help manage individuals potentially exposed to a threat agent.