Hatsudai Index, completed in 1987, stands as a notable example of 1980s Japanese commercial architecture. Located in the Hatsudai district of Shibuya, Tokyo, this office building was designed by the Yoshihiko Osugi Architectural Institute. The structure exemplifies the architectural trends of the Bubble Era, reflecting contemporary design principles and urban development approaches of that period. With its distinctive form and thoughtful integration into the surrounding streetscape, Hatsudai Index represents an important chapter in Tokyo's ongoing architectural evolution and remains of interest to those studying late twentieth-century Japanese office building design.