Our daily life and economic activities are built on various social infrastructure. This infrastructure includes roads, railways, aircraft and watercraft, electricity, gas, waterworks, telecommunications, and the Internet. We take these social infrastructures for granted as we enjoy the convenient and comfortable lives they provide for us. Social infrastructure consists of public works and structures like tunnels, dams, and highways. We at Kumagai Gumi have been involved in creating numerous social infrastructure creation projects. Once completed people might take this work for granted, but we are strongly aware public nature and heavy responsibility of these projects and so we give our all to successfully completing them. Kumagai Gumi has technical ability that has been polished for over a century.