Structural and multidisciplinary optimization continues to play a crucial role in advancing both theoretical research and practical engineering applications. Building on the legacy of the previous ACSMO congresses-held in Nagasaki (2016), Dalian (2018), Seoul (2020; Online), Matsue (2022), and Zhengzhou (2024)-ACSMO 2026 aims to further strengthen academic collaboration and promote cutting-edge developments in this vibrant field.