A new system named Science and Technology Knowledge Platform (STKP) is being realized in Japan with support of he national government. This paper describes the architecture of STKP and compares it with the old national science and technology (S&T) system. STKP provides an open platform for communication among scientists, engineers and even investors. They can enter STKP after registration from the portal site provided by the Research Institute of Economy, Trade and Industry (RIETI.) They submit S&T information to STKP via the portal, and the information is stored in a database. Users may search and obtain useful information from the database usually for no charge. STKP participants can freely create discussion forums on not only technical but also policy issues. The Engineering Academy of Japan and related S&T institutions have collaborated to create STKP.