The digital information and communication infrastructure as empowered by Internet technology has already become an indispensable platform of people’s daily lives activities and working environment. The information and communication networks that had been based on voice communication infrastructure until the late 1990’s could not provide a broadband, always-on communication environment to end users. On the other hand, a new type of information infrastructure using the native Internet technology such as ADSL and wireless LAN has begun to deployed rapidly. When the Japan Gigabit Network (JGN), most Internet connections used over 64Kbps class narrowband dial-up connections. Thus, the information and communication infrastructure was a primarily narrowband system and today’s broadband environment has not yet explored. It was under these circumstances that the JGN was initiated to create an environment enabling research and development of the infrastructure, middleware, and application technologies that would become necessary when a gigabit class network environment was introduced, and to accelerate this research and development. This publication will show that the JGN project has achieved many fruits, both domestic and international, academic and industrial. The source of these successes lies in the fact that the JGN provided an environment where the results of researchers’ efforts are tested and evaluated in actual and practical use, and that the architecture and operation of this environment was in turn performed directly by the researchers themselves. Thus, the continuous operation of a new IT infrastructure on a trial basis has proved an exceptionally valuable policy for the promotion of Japan’s information and communication technology research.