As a result of already established networks, the resilience of the community response to the WTC disaster was effective even though the Emergency Operations Center at the WTC had to be evacuated following the attack and subsequent building collapse in late afternoon. Both the management and the conduct of emergency-response activities continued uninterrupted through the most intense phase of the crisis, despite significant communications disruptions and having to deal with the massiveness of an unforeseen disaster. The effectiveness of the response in the face of the many impediments experienced was due to resiliency that was able to mobilize and coordinate the multiple resources of public and private agencies. Using data from the FEMA (Federal Emergency Management Agency), the various organizations that were part of the network that responded to the WTC disaster were nonprofit organizations that included religious groups, medical clinics, food services, legal organizations, and various volunteer organizations; private organizations, that included Consolidated Edison, the New York Stock Exchange, Prime Power, John Deere, MapInfo Corporation, and United Parcel Services; and public-sector emergency management agencies. The author’s analysis of the response to the WTC disaster is preceded by a literature review of the theoretical foundations for the study of interorganizational networks in emergencies. The review focused on the theoretical framework drawn primarily from dynamic network theory, complex adaptive systems theory, and social capital theory. Together, these theories provide insights into interactions among organizations, and they identify features of successful interorganizational networks in emergencies. 1 figure and 29 references