Abstract: Dynamic Team Management for Cross-organization Collaboration was developed by IBM, in cooperation with the U. S. Defense Information Systems Agency (DISA) and MITRE (a federally funded research and development organization), to support participating organizations in the U.S. Homeland Security/Homeland Defense Command and Control Advance Concept Technology Demonstration (HLS/D C2 ACTD). Dynamic Team Management includes finding and accessing information about resources (people) with whom you need to communicate and collaborate on a mission or task. Used in conjunction with collaboration tools and other applications, DTM supports constructing cross-organization teams of individuals to address particular missions or tasks, based on emerging needs. DTM demonstrates approaches to overcoming many of the challenges of building the best teams for each mission/task, accommodating information sharing preferences of participating organizations, directory integration automation, dynamically scaling to meet cross-organization communication and collaboration requirements, and achieving organizational interoperability.