Bruce Crouch, the current managing director of the London agency, will carry on as the executive creative director alongside the global creative director, Paul Shearer. The news comes amid rumours that Crouch is to leave Nitro to pursue other interests. Crouch has denied this.
Based in London, Fourie will be responsible for running Nitro London and Nitro's new ventures in Moscow, Germany and Dubai.
Fourie was responsible for the management of Nissan and the global management of the Chivas Regal accounts at TBWA\G1 Paris. He also spent four years as the chief executive of TBWA\Singapore, and has worked at D'Arcy, Lintas and Publicis.
Chris Clarke, the chairman of the Nitro Group, said: "He is one of the best strategic thinking suits in the business."
Crouch added: "Johan will bring the account management and business skills that our business requires."