Management of large-scale disasters is impeded by inadequately designed organizational infrastructure. The vertical organizational structures of most agencies responding to disasters contribute to a poorly integrated response, especially when collaboration, information sharing, and coordination are required. Horizontal (or lateral) organizations have assisted traditionally vertical civilian and military agencies by enhancing their capacity to operate successfully in complex human emergencies and large-scale natural disasters. Because of the multiagency and highly technical multidisciplinary requirements for decision-making in chemical and biological disasters, similar horizontal management options must be considered.