Through what processes do complex organizations in Japan decide to adopt new technologies ? Through adopting and utilizing new technologies, what changes come to develop within the organizations ? "Computer" as an electric data-processing system is the new technology which this paper is concerned with. It has been more than twenty years since computer technogies were introduced to the management of Japanese industrial organizations. However, very little is known about the adoption processes of computer, the development processes of computer-based information system, and the impacts upon organization management. This paper, examining the historical development of the computer adopting and utilizing processes within Tokyo Gas Co. Ltd. (the largest gas supplying company in Japan), tries to explore these unknown questions.