In 2005, Mr. Kamei has been promoted to President and CEO of Nikken Sekkei company where he works since 1981. His works vary from large scale office buildings to complex mixed-use developments. He has been working for Japaneese major developers such as Mitsui Fudosan, and major corporate clients like YKK, Japan East Railways and overseas developers as Pacific Century Group (HK). His major works are YKK 80 Building-headquarters office building, Midland Square-office and commercial complex in Nagoya, Queen's Square Yokohama — large mixed-use development and Tokyo Yaesu Station Development-redevelopment on Tokyo Station.
Tadao Kamei got a number of awards: Building Construction Society Awards (2003, 2014), Ashihara Yoshinobu Award Mention (2006), Japan Institute of Architecture Fine Architecture Selected Work (2007), Kanagawa Architecture Concours (2012), Association of Railway Architects Prize (2014), the Prize of Architectural Institute of Japan (2015).