- 1971 Landscape Architect, Landscape design firm in Kyoto, Japan
- 1975 Apprenticeship under traditional Garden Master
- 1981 Director, Japan Landscape Architecture, Inc. in Maryland.
He moved to the East Coast (Washington, D.C. Metropolitan Area), U.S. and operated his own Company.
- 1990 The Project manager, Peter Walker and Partners in San Francisco.
Hiko Mitani was requested from Peter Walker to work at his office.
- 1998 The general manager of Landscape design group and the chief landscape architect, Nikken Sekkei Ltd.
- 2009 Chief Exective Officer, Mitani Landscape studio, Inc.
AWARDS 三谷康彦 受賞歴
- 1985 Awarded the Grand Prize "The I.M.F. and the World Bank Joint Library Courtyard"
- 1985 Awarded "Boland Trane Company Head Office Landscape"
- 1990 Honorable Mention Awards "Bennett Residence"
- 1998 ASLA MERIT AWARD "Toyota Municipal Museum of Arts w/Yoshio Taniguchi"
- 2004 ASLA MERIT AWARD "Saitama Plaza"
- 2006 Japanese Institute of Landscape Architecture Grand Prize "Kyoto States Guest House"
- 2006 International Lighting Design Award "Kyoto States Guest House"
- 2010 IFLA APR AWARD OF EXCELLENCE 「Kyoto States Guest House」