Heiseikan, which commemorates the marriage of His Imperial Highness, is a museum built next to the main building. It is intended as a special exhibition venue solely for temporary exhibitions. Our aims were to create: 1.A bright and dignified commemorative building suitable for the Heisei era, that had the character of the start of the era and used the highest level of building technology that had been completed in the Showa era. 2. A building to harmonize with the environment of Ueno forest and the other existing buildings. 3. A building with superior performance, able to safely store and exhibit collection items in the longer term. We achieved “expression of the character of the Heisei era” and “superior performance” through detailed studies at the design stage, and close collaboration between the client, users, designers, builders, and manufacturers over quality control up to the completion of construction. At Tokyo National Museum, we are carrying on our work, to pass the value of Japan’s leading artistic and cultural site to future generations. Other than the design for remodeling the Heiseikan exhibition rooms 15 years after completion, we are refurbishing facilities within the building, as well as new construction.