The Office of Defense Nuclear Nonproliferation Research and Development (NA-22) has a research objective to: Develop alternative technologies that reduce the risk from the malevolent use of high-activity radioactive sources. This objective focuses on the R&D needed to replace high activity radioactive sources that are deemed to pose a significant risk if malevolently used. Our current emphasis is on emerging and innovative technologies and techniques for the replacement of these sources with non-radioisotope based technologies. Radioactive sources serve a number of critical functions including the treatment and diagnosis of disease, the inspection and certification of critical mechanical structures, the sterilization of food and medical products, and the exploration for petroleum. Replacements or alternatives proposed must provide equivalent (or improved) functionality and be less susceptible to malevolent use. Each proposal must address: economic feasibility of the proposed alternative or replacement, ease of maintenance (both the equipment and the source) and relative accessibility in and around the device.