The technology trend was surveyed to clarify the themes of smart structural system towards its R and D. The smart structural system is a structural system which incorporates functions of perception, judgment and learning by integrating functions, structures and information, to ensure the structural soundness at real time and control the active-adaptive of shapes. The final goal of it is to make materials and structures similar to organic systems. It has a self-repair function which can detect the generation and propagation of cracks and prevent the destruction positively with conducting self-diagnosis. High performance, high efficiency and energy saving are expected by combining the conversion of design concept into destruction control and the regulation of vibration, noise and shape. Especially, it is effective for the safety of aerospace systems, earthquake disaster measures, and extension of machine life. This report describes the background, purpose, R and D activities in Japan and foreign countries, and basic development themes. In addition, it arranges the needs of various industrial fields systematically, and proposes a concrete concept. Furthermore, the effects expected by the application of smart structural systems and the outline of international technical cooperation are presented. 110 refs., 164 figs., 19 tabs.