Nurses are the largest group of healthcare providers and will be at the forefront during a response to a bioterrorism attack in the U.S. However, nurses' bioterrorism risk perceptions and their participation in bioterrorism preparedness activities, such as bioterrorism-related exercises or drills, have not been evaluated. We mailed a survey to all members of the Missouri Nurses Association in July 2006, consisting of 1,528 registered nurses. The instrument measured risk perception, perceived susceptibility, perceived seriousness, bioterrorism education received, participation in exercises/drills, and personal response plan thoroughness. The response rate was 31% (474/1,528). Most respondents believe that a bioterrorism attack will occur in the U.S. (82.3%; n = 390), but few (21.3%; n = 101) believe that one will occur in their community. The majority of nurses reported that they believe that a bioterrorism attack would have serious consequences (96.1%, n = 448), including having a serious impact on U.S. citizens' safety (90.7%, n = 446) and on their own safety (84.3%, n = 379). Most (60%, n = 284) reported that they had not received any bioterrorism-related education nor participated in any drills/exercises (82.7%, n = 392). Of those who had received education, most had participated in 3 or fewer programs and in only 1 drill. Few nurses (3.6%, n = 15) reported having all aspects of a personal bioterrorism response plan; approximately 20% (19.4%, n = 81) did not have any components of a plan. Most of the registered nurses in Missouri who were surveyed are not receiving bioterrorism education, participating in bioterrorism exercises, or developing thorough personal response plans. Nurses need to be aware of and encouraged to participate in the many education and training opportunities on bioterrorism and infectious disease disasters.