Book excerpt: Construction of seventh carbon-ion therapy facility in Japan, East Japan Heavy Ion Center, Faculty of Medicine, Yamagata University, is near completion. The building is 45 m u00d7 45 m u00d7 27 m cubic design, smallest facility in the world, and connects directly to general hospital. A main synchrotron accelerator (a maximum energy of 430 MeV/u) with newly designed dipole magnets is located on the basement floor. There are two treatment rooms, horizontal and 360u02da rotating gantry, on the 2nd floor. Rotating gantry is even smaller than NIRS gantry using the superconducting technique and shortened scanning system. We chose RayStation (RaySearch Laboratories AB) as the treatment planning system which has very fast dose calculation engine to accurately calculate dose. In 2019, building construction and system installation will be completed, and acceptance testing and clinical commissioning will begin. After the commissioning work, first patient will be treated in spring 2020.