In Yamaguchi a key person responsible for specific projects, carries out all his works, from gathering information relative on his works to technical and development support to possible customers to even sales, all integrated with one another, in order to make it possible to stably supply "Goods of Value" to customers.

By making full use of the company's functions as a international trading company, he can collect as much useful information as possible through what we call "stretched antennas" around the globe, update and living information that will be given to the customers.

Under close relationship with API manufacturers, which aim at taking maximum advantage of each and every innovation-derived from in-house research and development of new products, he also makes active efforts to perceive and understand customers' needs, having the manufacturers reflect them in the quality of the new products, as well as he has it in mind to fully support the customers concerning the use of the new products. Under the close contacts with customers it is, Yamaguchi believes, the fundamental duty to concentrate its energies on all its works, taking one step forward at all times.