This report is designed to aid state, territorial, tribal, and local public health leaders as they improve their capacity to achieve situational awareness during a public health emergency. We intend this report to serve as a concise reference work public health leaders can use to help design and manage biosurveillance systems to be used during an anticipated public emergency. This report lists “core” information needed to effectively manage the public health aspects of an event such as an outbreak, a natural disaster, or a mass gathering. Furthermore, the report describes guiding principles and system capabilities that assure surveillance information systems meet relevant standards, while addressing the need for flexibility to adapt to unique and changing circumstances.