[2] With the turn of the century approaching and a digital revolution about to transform the industry, Diesel merged with Stratège Media in 1999 and added Martin Gauthier and Daniel Fortier to their management team.

[4] In the midst of this partnership, the agency opened offices among the hustle and bustle of Amsterdam in 2008 and Paris in 2009, in what Bertrand Cesvet described as “a semi-controlled whirlwind of boundless enthusiasm.” In 2009, Sid Lee realized that the future of retail depended on a brand’s ability to attract customers to its stores and the way it interacts with its consumers.

During the 2013 Cannes Lions Festival, the firm announced the launch of Sid Lee Entertainment, aimed at creating engaging experiences and content for its clients.

On July 6, 2015, Sid Lee was acquired by kyu,[9] the strategic operating unit of the Japanese Hakuhodo DY Holdings, which is currently headed by CEO Michael Birkin.

In 2019, Sid Lee continued its expansion into the United States[11] as Hornall Anderson, Infrared and Red Peak joined the agency.