Several large-scale accelerator facilities are operational or under construction in Korea, such as the Korea Multi-purpose Accelerator Complex (KOMAC) in Gyeongju, the 3rd Generation Synchrotron Light Source (PLS-II) and the X-ray Free Electron Laser (PAL-XFEL) in Pohang, the Rare Isotope Science Project (RISP) in Daejeon, and the Korea Heavy Ion Medical Accelerator (KHIMA) in Gijang (plus a new 4th Generation Storage Ring is being planned in Cheongju). By using advanced beam physics models and simulation tools, cutting-edge beam diagnostics, and sophisticated beam manipulation techniques, we aim to optimize and improve the performance of those accelerators. Furthermore, we will try to develop transformational technologies for the next-generation high-intensity accelerators such as the International Fusion Materials Irradiation Facility (IFMIF), Accelerator Driven System (ADS), and Heavy Ion Fusion (HIF). Applications of the accelerators to laboratory astrophysics and cancer therapy will also be actively pursued.