1. Name of Database: Ionosphere Database 2. Institution: World Data Center for Ionosphere, Communications Research Laboratory 3. Contents of Database: The ionosphere database is constructed with ionospheric data observed in Japan and ionospheric data obtained in various countries since IGY period. Ionogram observed in Japan is provided in realtime by Web ( http://wdc.crl.go.jp ). Data catalog and ionospehric data book are also published. 4. Examples of Database: Example of ionogram at Wakkanai, Kokubunji, Yamagawa and Okinawa Example of ionospheric variations (foF2, fEt, h’F and h’E) observed at Kokubunji 5. Contact: K. Igarashi Communications Research Laboratory TEL:+81-42-327-7478, FAX:+81-42-327-6659 E-mail:igarashi[AT]crl.go.jp 6. Public Offering Database: