As the host country of the 2025 World Exposition, Japan (Osaka-Kansai Expo), which will be held under the theme of "concept design a Future Society for Life," this pavilion, based on the theme "Between Life and Life," seamlessly connects displays and architecture, allowing visitors to experience the significance of "circulation." The Japan Pavilion, with its circular structure embodying the relay of life, exudes a unique presence as a pavilion of a host country. While the flow of visitors is naturally drawn into the pavilion as they walk around it, its most distinctive feature is the countless wooden planks arranged in a circular pattern. The gaps between these planks allow visitors to glimpse the interior, and the continuity between inside and outside, displays and architecture, encourages visitors to become aware of the "in-between" aspect of the pavilion's theme. Another unique feature of this pavilion is the concept of a "Japan Pavilion that eats garbage." Microorganisms will decompose waste generated within the Expo site and convert it into energy and water. This "living pavilion" allows visitors to relive this process through an installation* and experience how the energy and water generated power the Japan Pavilion. By circulating the three-zone pavilion, visitors can sense the significance of "circulation," a Japanese aesthetic, and truly feel part of this long and magnificent story. Additionally, by using primarily cross-laminated timber (CLT) as "wooden boards" and steel for the structure, the pavilion uses CLT in as simple and symbolic a way as possible. The CLT used in the Japan Pavilion is planned for reuse by companies and local governments across Japan after the Expo ends, and has been designed for easy dismantling and repurposing. By understanding the value of "circulation," which underlies the Japan Pavilion's theme, "Between Life and Life," we aim to encourage visitors to reexamine the circulation that surrounds us and explore the future of society and hints for a sustainable future. Our company is responsible for displays concept design (schematic design, working drawings), construction, and operation of the Japan Pavilion. *A contemporary art form in which the entire displays space is experienced as a work of art. The audience walks around the space and enjoys the work through sights, sounds, and more.