The trend of retail concentration across the European Union has raised concerns on the buyer power that retailers may have in the relation with their suppliers. Following calls that the changing nature of competition demands a change in EU competition policy, this book investigates whether there is a ‘gap’ in current EU competition law concerning the potential harmful effects of buyer power from an economic efficiency perspective. Using a Law and Economics approach, the author identifies the potential concerns and assesses whether they can be addressed under the existing rules. While some critical comments are in place with regard to the consumer welfare standard that is applied, the author’s analysis does not indicate that the current substantive legal framework of EU competition law is unfit to address the (potential) harmful effects of buyer power.