The section on the challenge of biological terrorism focuses on the importance of an effective threat assessment. The key components of the proposed threat assessment involve an examination of "who" (the actor), the "what" (the agent), the "where" (the target), and the "how" (the mode of attack). These key components are integrated into a "matrix-pathways" approach to develop a representation of the complex nature of the bioterrorism threat. The application of the "pathways" methodology yielded several important findings that should inform efforts to develop an effective health and medical dimension to the Nation's overall capabilities to respond to bioterrorism. The section on the public health and medical responses to bioterrorism focuses on the major functions of the public health and medical response system; namely, surveillance, epidemiology, laboratory capability, medical management, training and education, and information and communication. The discussion of each of these functions identifies the requirements that must be met if the function is to be performed effectively. Further, the key issues associated with each component are discussed, and recommendations are provided. The report also discusses another aspect of public health and medical response to bioterrorism; i.e., the organizing and coordinating of national efforts among responsible entities at the Federal, State, and local levels to prepare and execute the public health and medical system in the event of a bioterrorism attack. The main issues discussed are the nature and success of preparedness efforts of Federal, State, and local entities; the need to develop a strong partnership between the private and public sectors; and the structure and organization of the Centers for Disease Control and Prevention's bioterrorism preparedness and response program. Based on the material covered in the main sections of this report, it concludes with general findings and recommendations for the development of a comprehensive, multifaceted, coordinated nationwide preparation for a response to a bioterrorism attack. Appended 800-item bibliography and information on site visits and interviews