It was placed in the each market east and west of the capital, and Higashi no ichi no tsukasa (Office of the East Market) belonged to Sakyoshiki (Eastern Capital Offices) and Nish no ichi no tsukasa (Office of the West Market) belonged to Ukyoshiki (Western Capital Offices).
都の東西の市場それぞれに設置され、東市司（ひがしのいちのつかさ）は左京職に西市司（にしのいちのつかさ）は右京職に属していた。