Tanaka previously launched independent boutique agency GT with Koshi Uchiyama in 2000. Tanaka will continue at GT as a board member. He also spent twenty years at Dentsu in working with major clients including Toyota Motors, Sony, NTT, Fuji Film and Ajinomoto. He was behind One Sky and headed the agency as president when Dentsu in Japan expanded into the boutique agency arena.
At GT, Tanaka is best-known for his work 'Love Distance' and Uniqlo, which won a gold and a silver at Cannes Lions and One Show respectively.