AbstractThe Japan Atomic Energy Research Institute (JAERI) has been conducting the design and the related technological research and development (R&D) of a D—T burning tokamak fusion reactor, named Fusion Experimental Reactor (FER), aiming at demonstration of the feasibility of fusion power. In parallel with the domestic program, the conceptual design of the International Thermonuclear Experimental Reactor (ITER) has been successfully completed through the united efforts of four parties. Based on these achievements, research and development work is being initiated as the Engineering Design Activity (EDA), which involves manufacturing and testing of scalable models to demonstrate engineering feasibility. This paper describes the design concepts of ITER and the relating key technology of the superconducting magnet and remote handling being developed at JAERI.