Kumagai Gumi Co Ltd is a Japanese company that provides services in construction and civil engineering. The company analyzes, designs, and supervises complex construction projects. It also offers engineering and technical services throughout the construction process. These projects include roads, railways, airports, water systems, and other public facilities. In addition, the company is engaged in manufacturing and selling construction materials and machinery. Construction activities account for the majority of revenue. The company generates additional revenue from developing residential and commercial complexes and either operating the building or acting as a broker and selling the real estate.