Georges Plassat officially joins Carrefour today after being appointed as chief executive of the struggling French supermarket giant in January.

The former head of French clothing retailer Vivarte will initially work as chief operating officer alongside outgoing CEO Lars Olofsson before taking over the top job in June.

Plassat will become Carrefour’s fourth CEO in eight years. The French supermarket has struggled in recent years amid tough price competition from domestic rivals and the decline of the hypermarket format. 

The departure of Olofsson after three years comes after a particularly difficult 2011. The company’s share price tumbled by 40% after five profit warnings were posted over the course of the year.