An important building in both size and stature, the Shinjuku Sumitomo Head Office is an integral part of the Shinjuku skyline. Its three-sided footprint makes good use of available space. But at the same time, the building's design sacrifices valuable floor space by offering a massive atrium running the entire height of the building. In a further concession to making the building more human-friendly, the triangle corners have been cut off, allowing even more exterior windows.