The events of September 11th, 2001 have demonstrated the need for better preparedness in the event of another terrorist attack here in the United States. It is well demonstrated that problems of response and the delivery of services during the hours and days immediately following the attacks at the World Trade Center were due, in part, to poorly integrated workflows. We must learn from the mistakes and deficiencies of the past, while bringing to bear the latest advances in the field, when developing support systems to be used by first reponders. This research and the development work described herein, particularly in the area of inter-organizational workflows, attempts to address some of these deficiencies. Previous research at Monmouth University has studied the operations of Incident Command Centers and has resulted in the development of an intuitive tool to model dynamic workflows for these centers. This tool, however, was designed as a standalone application that did not allow for the interaction among workflows. A significant reengineering effort, described in this work, was undertaken to convert the aforementioned standalone tool to a distributed architecture that supports inter-organizational workflows and allows for future growth. A workflow engine was created to execute both modeling and enactment of interorganizational workflows. Web services were developed to expose engine functionality to clients. A persistency model was introduced for storing both the workflow models and instances. A primitive role-based access to the workflows was added for security purposes. Three types of inter-organizational workflow communication were identified: notification, asynchronous and synchronous. The implementation described herein supports all three of these communication types. The Workflow Mangement Coalition Reference Model was used to focus the architecture and design of this tool.