Britain’s newspaper and magazine publishing business did not fare particularly well during the 1950s. With leading newspaper proprietors placing their desire for political influence above that of financial performance, and with working practices in Fleet Street becoming virtually ungovernable, it was little surprise to find many leading periodical publishers on the verge of bankruptcy by the decade’s end. A singular exception to this general picture of financial mismanagement was provided by the chain of enterprises controlled by Roy Thomson. Having first established a base in Scotland in 1953 through the acquisition of the Scotsman newspaper publishing group, the Canadian entrepreneur brought a new commercial attitude and business strategy to bear on Britain’s publishing industry. Using profits generated by a string of successful media activities, in 1959 Thomson bought a place in Fleet Street through the acquisition of Lord Kemsey’s chain of newspapers, which included the prestigious Sunday Times. Early in 1961 Thomson came to an agreement with Christopher Chancellor, the recently appointed Chief Executive of Odhams Press, to merge their two publishing groups and thereby create a major new force in the British newspaper and magazine publishing industry. The deal was never consummated however. Within days of publicly announcing the merger, Odhams found its shareholders being seduced by an improved offer from Cecil King, Chairman of Daily Mirror Newspapers, Ltd., which they duly accepted. The Mirror’s acquisition of Odhams was deeply controversial, mainly because it brought under common ownership the two left-leaning British popular newspapers, the Mirror and the Herald. The current paper utilises archive sources from the Cabinet Office to explore the political dialogue that enabled the controversial takeover to proceed unopposed by the regulatory authority of the Monopolies Commission. In business terms, it analyses the implication of the successful prosecution of the deal for magazine publishing in Britain: the creation of a virtual monopoly through the formation of the Mirror-controlled IPC Magazines, and Thomson’s hostile response to this new enterprise spearheaded through his ownership of the Sunday Times.