Radiation Research: Biomedical, Chemical and Physical Perspectives documents the proceedings of the Fifth International Congress of Radiation Research held in Seattle, Washington, 14-20 July 1974. While the focus of the Congress was on fundamental research, there were several well-attended sessions on the practical aspects of radiation research as it relates to radiotherapy, central station power generation by both nuclear fission and fusion, and the environment. This volume contains 126 papers organized into 31 parts. Beginning with a keynote address and a lecture on the time scale in radiobiology, the subsequent contributions cover a wide range of topics presented over several sessions. Topics discussed during these sessions include energy needs, nuclear power, and the environment; prospects for fusion power; technological applications of radiation; human radiobiology; hazards of radiation exposure relative to other environmental agents; the basic physics of the interactions of radiation with matter; particle penetration phenomena; and radiation effects in frozen media.