||Emergency Response involves multiple organizations and teams, geographically distributed operations, and a high need for coordinated control and decision making. As incidents evolve, the number of involved organizations, the geographic distribution of involved entities, and the level and complexity of decision making all tend to grow. Information technology can contribute to managing these and related dimensions of an emergency. The work described in this paper is based on longstanding MITRE Corporation experience working with organizations that have severe and demanding requirements for managing complex, rapidly evolving situations, including military conflict, law enforcement engagements, natural disaster response, and terrorist incident response. Recently, we have conducted a series of detailed observations during emergency response exercises and planned events that resulted in identifying key elements for a successful application of information technologies during an emergency. Â© Proceedings ISCRAM 2004.