The study objectives were to compare local public health professionals' bioterrorism risk perceptions, the extent of bioterrorism preparedness training, and to describe preferred methods for delivery of preparedness education in the United States. National needs assessments were conducted via a mailed survey to 3,074 local public health departments in October 2000 and November 2001. Compared to a survey conducted in October 2000, the perceived risk of a bioterrorism attack in the United States increased dramatically after September 11 (p < 0.0001); however, 57% of respondents believed one was unlikely to occur within their own community. Public health professionals perceive their own communities to be at low risk for a bioterrorism event. Ongoing, updated, standardized bioterrorism preparedness education is needed.