Ben Fennell, the UK chief executive at BBH, said: "The CSO role will focus on two key deliverables, relentlessly improving the quality and efficacy of the work, and better translating that work into great growth."
Gonsalves and Bottomley’s current department head positions will be filled by BBH planning directors Kirsty Saddler and Dan Hauck. Saddler and Hauck will now lead a 30-strong department.
In addition, the agency has hired Tom Roach as a planner. Roach joins from Leo Burnett, where he headed up the McDonald’s account.
Bottomley has been at BBH for eight years and first joined the agency from TBWA. He runs key account for the global Axe/Lynx business, which has won awards including the Grand Prix for Effectiveness at Cannes in 2012.
Gonsalves has been with BBH since 2006 and was made joint head of planning with Bottomley in 2008. He has run BBH accounts including The Guardian, Google and Asos.
Prior to BBH, Gonsalves was at comms planning agency Michaelides and Bednash, where he was a partner running Channel 4 account.