It follows news that James Parsons - who has led the operation for the past five years, either solely or with one-time fellow co-CEO Jason Frank – is to leave in June.
MSL London strategic development director James Warren will lead the agency until McCafferty joins on 16 September.
McCafferty will be responsible for leading MSL’s 200-strong London business. He will report to Annette King, UK CEO of MSL owner Publicis, and Guillaume Herbette, global CEO of MSL.
MSL Group said: "McCafferty will work with MSL’s leadership team and other agencies within Publicis Groupe UK to help accelerate growth for MSL and work even more closely with other Publicis Groupe agencies to better serve clients through the Power of One. He will also collaborate with MSL leaders across the MSL global network to support multi-market growth opportunities."
McCafferty is the founder of Kaper, the PR agency that is part of marcoms group Karmarama – that company was acquired by Accenture in 2016.
The Kaper name was dropped last year, as McCafferty moved to a new role as MD of Accenture Interactive’s UK Experience Agency operations.
McCafferty previously worked at Shine Communications and MSN.
King said: "We are delighted to have Chris on board. With his experience in collaborating closely across specialisms to ensure data driven PR and activation in a digital world, he will be brilliantly positioned to helping drive the Power of One model in the UK.
"I would like to thank James for his commitment and outstanding service at MSL London. He has been instrumental in the success of the agency and we wish him all the best in the future."
MSL London generated revenue of an estimated £37.5m in 2018, a rise of four per cent on the previous year, according to PRWeek’s UK Top 150 Consultancies table.