Preparing for the unknown, responding to the known: communities and public health preparedness.

More than four years after September 11, 2001, bioterrorism preparedness remains a high priority for federal, state, and local governments. With reasonably flexible federal funding, communities have strengthened their ability to respond to public health emergencies, according to assessments by stakeholders and market observers. Collaborative relationships developed for bioterrorism preparedness have proved useful in addressing other threats, such as natural disasters and infectious disease outbreaks. Major ongoing challenges include funding constraints, inadequate surge capacity, public health workforce shortages, competing priorities, and jurisdictional issues.