The Civil Nuclear Energy Research and Development Working Group (CNWG) held its sixth annual meeting on May 24, 2018 in Osaka, Japan to facilitate bilateral cooperation on advanced nuclear technology R&D. The CNWG was jointly established by the U.S. Department of Energy (DOE), Japan’s Ministry of Economy, Trade and Industry (METI), and Japan’s Ministry of Education, Culture, Sports, Science and Technology (MEXT). In addition, participants from Japan included the Japan Atomic Energy Agency (JAEA) and Japan’s Central Research Institute of Electric Power Industry (CRIEPI). During the meeting, the experts from U.S. and Japan reported on their recent cooperative efforts and agreed to enhance collaboration on nuclear R&D in various fields, including fast reactors, high-temperature gas reactors, nuclear fuel cycle and waste management, and light-water reactors. DOE, JAEA, and CRIEPI also jointly launched a new project to conduct safety analysis on metal-fueled fast reactors.