International humanitarian aid and development organizations active in the Democratic Republic of Congo (DRC) are faced with an ongoing crisis situation. Using any formal or informal information source available, they are constantly acquiring and processing information that may indicate the possible surge of an acute crisis. Information systems (IS) that enable effective and efficient information processing and decision making within and among the organizations are therefore a critically important asset to these organizations. We present a concise set of design premises that have been developed for dynamic emergency response management information systems, and we introduce the theory of Sensemaking as a lens to observe and analyze the information processing and decision making behavior of organizations. Based on interviews conducted among senior management of international aid and development organizations operating in the DRC, our findings illustrate the constant Sensemaking behavior of these organizations and provide a motivation for the proposed IS design premises. © 2008 Wiley Periodicals, Inc.