Agency MD Hoon Kim will assume managerial responsibilities, while the search is underway for an ECD to work alongside him.
Simon Sherwood, chief operating officer of BBH Group, said: “We are not looking for a direct replacement chief executive. We will use the MD/ECD model and see how it goes.”
Yamaguchi was hired to win more domestic business for BBH Japan. The latter part of his career was spent at Dentsu subsidiaries in Europe and the Americas as deputy director of the international management division.