According to Homeland Security Presidential Directive 10 (HSPD-10): Biodefense for the 21st Century, a national bioawareness capability providing early warning, detection, or recognition of a biological weapon attack is an essential component of biodefense. To contribute to this national capability, the Department of Homeland Security (DHS) operates the BioWatch program, which uses routine laboratory testing designed to detect an aerosolised biological attack for five specific biological agents considered high risk for use as biological weapons. The BioWatch program is a federally-managed, locally operated system with collectors deployed primarily in outdoor locations in more than 30 major metropolitan areas. This book provides an overview of the BioWatch Generation-3 Acquisition program with a focus on meeting mission needs for effective biosurveillance.