Research Organization for Information Science and TechnologyResearch Organization for Information Science and Technology (RIST) is a general incorporated foundation which has been carrying out usage promotion services of the High-Performance Computing Infrastructure (HPCI) of Japan, commissioned by the Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT). HPCI is a world top-class supercomputing environment with Fugaku and supercomputers from Japanese universities and research institutes connected by a high-speed network. The RIST has taken a role as the operation office of the HPCI. Within a framework of them, we are in charge of managing HPCI shared use computational resources and promoting usage., i.e., projects selection, user support, and dissemination of research outcomes.