Design, operation and commissioning are important stages through buildings’ life cycle. This talk will review Liping’s simulation efforts and key findings in those three areas. She will describe a series of connected projects including design of naturally ventilated buildings, building-integrated mechanical systems, evaluation of the operation impact on building energy use, automatic fault detection and diagnostics, and ongoing commissioning for an existing office building. Critical R&D to accelerate the integrated framework using building simulations for an innovative building design, operation, and commissioning process with lower life-cycle costs will also be discussed.