The Co-operative Group has retained Leo Burnett as its ad agency. The company called a review in November last year and the pitch process was handled by AAR. Leo Burnett beat WCRS in a final shoot-out. MullenLowe London and Ogilvy & Mather London also met the Co-op at the start of March. The Publicis Groupe agency also handles The Co-operative Bank, which was not part of the review. Rocket holds The Co-operative Group’s media planning and buying account.