The Geographical Survey Institute (GSI) is preparing the establishment of Japan's new geodetic datum, Japanese Geodetic Datum 2000 (JGD2000), and its realization, Geodetic Coordinates 2000, based on a geocentric system. This review paper focuses on historical background regarding the establishment of geodetic datums and the present situation of Japan'sdatum to help readers understand the idea of, and background for the move to the new geodetic datum.
