The use of autonomous responsive dimming glass for energy conservation in office buildings by solar shading and daylighting is investigated through preliminary experiments, simulations, measurements, and questionnaires. It is shown that an appropriate configuration of the thermotropic (TT) glass, air gap, low-emissivity (low-e) coating and specified phase-change temperature provides, despite being a relatively simple system, large energy savings by shading solar radiation and making efficient use of natural light. Through practical application to a research institute building, the system is demonstrated to work well and to be considered by most occupants to improve the comfort in the office.