Gonsalves is currently the chief strategy officer at BBH London, where he has worked for ten years.
He will join Mcgarrybowen later this year and work with the joint executive creative directors, Angus Macadam and Paul Jordan, to grow the agency. He replaces Rick Hirst, who will become the UK chief executive at Carat.
In addition, Gonsalves will help develop Dentsu Aegis Network’s UK and Ireland creative proposition.
Gonsalves will report to Tracy De Groose, the Dentsu Aegis chief executive. She said: "Our aspiration is for Mcgarrybowen and Dentsu Aegis to be at the forefront of a new creative era. Jason’s blend of strategic thinking and creativity, combined with his deep digital expertise, make him ideal to shape our creative proposition."
Beginning his career in media at John Ayling & Associates, Gonsalves has also worked at Universal McCann and Michaelides & Bednash. He joined BBH in 2006 and was a head of strategy before being promoted to chief strategy officer in 2013.
Gonsalves will not be directly replaced at BBH.