The Sekai Kyuseikyo Headquarters Administrative Building, completed in 1977 in Atami, Shizuoka, represents a significant example of late twentieth-century institutional architecture. Designed and constructed by Takenaka Corporation, a renowned Japanese construction firm, this office structure exemplifies the modernist principles and engineering excellence characteristic of the period. Located in the scenic Momoyama district, the building serves as the administrative center for the organization. Its design reflects the architectural trends of 1970s Japan, incorporating functional efficiency with considered spatial planning, making it an important subject for architectural study and appreciation of post-war Japanese building practices.