Synchrotron radiation has become a unique tool for probing the structure of matter. It has a broad range of applications, not only in basic science (molecular and atomic physics, condensed matter physics, earth science, materials science, chemistry, molecular and cell biology, surface and interface physics, etc.) but also in medicine and in the industry (material investigation, lithography, micro-machining, drug design, etc.). With one third of the world sources, Japan leads the G-8 countries and is also the leader when it comes to "industrial sources". Japan is not building synchrotron sources solely to support basic research, it is building them because of the diversity, importance, and potential of high-technology, industrial applications of synchrotron radiation. Each source is an investment for the future, opening new research areas and calling for technical innovations. The purpose of this paper is to offer an overview of the japanese synchrotron radiation sources and their research activities. A special attention will be given to the development of industrial sources, as well as the application of synchrotron radiation to materials science.
