RRP has organized an informal group, Radiation Bioterrorism Research and Training (RABRAT), comprising representatives of federal agencies that have an interest in one or more aspects pertaining to radiological/nuclear terrorism: DHS, DoD, including the Armed Forces Radiobiology Research Institute (AFRRI), DOE, the Environmental Protection Agency (EPA), the Food and Drug Administration (FDA), DHHS, National Aeronautics and Space Administration (NASA), NIH (NCI, NIAID), the Nuclear Regulatory Commission (NRC), and the Radiation Emergency Assistance Center/Training Site. (REAC/TS). The purpose of RABRAT is to inform each other and coordinate activities among agencies, to avoid both duplications and gaps in efforts and funding. This effort has been helpful in developing a strong collaborative climate for radiation experts working in government and for the extramural research and development communities.