Following the attacks of September 11, 2001 and the anthrax letters, the ability to detect biological threats as quickly as possible became a top priority. In 2003 the Department of Homeland Security (DHS) introduced the Bio Watch programa federal monitoring system intended to speed detection of specific biological agents that could be released in aerosolized form during a biological attack. The present volume evaluates the costs and merits of both the current Bio Watch program and the plans for a new generation of Bio Watch devices. Bio Watch and Public Health Surveillance also examines infectious disease surveillance through hospitals and public health agencies in the United States, and considers whether Bio Watch and traditional infectious disease surveillance are redundant or complementary.