Compared to conventional "active" environmental control system, passive solar system is a better alternative option for thermal comfort conditioning inside the buildings. The judicious use of simple passive systems can significantly reduce the building's energy consumption for space heating, cooling, ventilation, and lighting. Hence, this chapter presents an overview of the major development of various building integrations of passive solar concepts such as Trombe wall, roof ponds, and BIPV/T. More importantly, their structures, working principles, as well as advantages and defects have been highlighted. On this basis, two types of