This paper evaluates the price effects of the merger of two major U.K. book retailers. We use a dataset containing monthly scanner data on a sample of 200 books in 50 local markets for four years around the merger. We compare the price changes after the merger in shops located in areas where both chains were present before the merger and in areas where only one chain was present. We also investigate the country-wide effect of the merger. We find that the merger did not result in any price increase either at the local or at the national level.