Comsys Holdings Corp installs electrical and telecommunications facilities and equipment. It provides solutions for information-process systems and develops software to fit the needs of customers. One division of the company connects telephone lines and other communication equipment and implements wireless base stations. It provides equipment for the mobile industry, and supplies maintenance work to transform telephone networks. Comsys Holdings has four business segments: NTT Engineering, NCC Engineering, IT Solutions, and Social System-Related and Other. It plans proposals for customers' systems integration and software upgrades and provides repair services to keep a system intact. The company has been instrumental in the development of Japan's telecommunications infrastructure.