When a new emperor ascended the throne, new Saio would be chosen by divination from the unmarried imperial princess and queens, enter a Nonomiya that had been constructed at a pure place in Sagano and undergo a year of purification before going to serve at Ise-jingu Shrine.
天皇が代替わりすると、未婚の皇女・女王の中から新たな斎王が卜定され、嵯峨野の清らかな場所を選んで作られた野宮に入って一年間潔斎した後に伊勢神宮へ向かった。