Since 1986, Mori Building Company Ltd. (Headquarters: Minato-ku, Tokyo; President and CEO:Minoru Mori) has been regularly conducting surveys of demand and supply trends of large office buildings with total office floor space of over 10,000 m2 (in this survey, they will be referred to as "large-scale office buildings") throughout Tokyo's 23 wards. Latest data (as of December 2005) became available; this summary report shows preliminary results of the survey.