Herbette is currently the global vice chairman of operations at FleishmanHillard, based in New York.
On 24 August, he will become the executive vice president of Publicis Worldwide, and chief executive of MSLGroup, the global PR network that Sadoun took over responsibility for in June.
He replaces Olivier Fleurot, who moves into a senior vice president role within Publicis Groupe. Saatchi & Saatchi’s worldwide chief operations officer Chris Foster is also moving to a senior vice president role at Publicis Groupe.
Part of Herbette’s remit is to help Sadoun create more seamless ways of working with all Publicis Groupe brands, such as Leo Burnett, Saatchi & Saatchi, Bartle Bogle Hegarty, Starcom Mediavest Group, ZenithOptimedia, Publicis.Sapient and Publicis Healthcare Communications Group.
Sadoun said: "Guillaume’s rich knowledge of the US market, global strategic vision, and valuable professional services experience are key assets that will contribute to MSL Group’s growth."
Publicis Groupe chairman and chief executive, Maurice Lévy, said: "I’m very pleased to have Guillaume on board as this will accelerate MSLGroup’s growth within our group through better integration with all our entities, providing them with the necessary complement of PR.
"This close collaboration with Publicis Worldwide will lead to the development of models that will be applied to all the Groupe’s entities."
In his role as chief executive, Herbette will be responsible for overseeing all MSLGroup businesses, including the global events offering through Publicis Live, PBJS and Publicis Events, as well as strategic communication consultancies such as Kekst & Company, CNC and JKL.
Herbette brings over 25 years of relevant experience to his new role. He joined FleishmanHillard in 1998, and assumed jobs of increasing responsibility throughout EMEA. He later served as chief operating officer for the firm’s US Eastern and Western and Canada regions. He took on vice chairman duties in 2010, where he was responsible for FleishmanHillard’s overall operations and growth.
Herbette began his career with PwC in 1991, in the company’s Paris office.