McLaren plans to leave the agency at the end of the year to ‘balance and broaden his portfolio of interests’.
However, he will continue to act as a senior consultant in leading H&K’s work for London2012’s Olympic bid and will continue to undertake a range of internal projects for parent group WPP.
He will also extend his outside interests with other companies and organisations, including the National Trust and cancer charity Maggie’s Centres.
McLaren, who began his career as a BBC journalist, spent around 25 years in the advertising industry before joining H&K as chief executive in 1994.
He became H&K chairman four years later and was responsible for developing and promoting its positioning as a multi-specialist agency.
European chairman Andrew Laurence – who assumes the UK chairmanship – said McLaren was a major contributor to the ‘look’ of H&K and the development of its corporate identity.
H&K CEO Mary Louise Windeler will now lead H&K UK, reporting to Laurence.