During World War II, the British ran a sustained anti-shipping cam-paign against Axis merchant and supply traffic in the Mediterranean. Although the effects of this on the land war in North Africa have been the subject of much debate, little attention has been paid to the nature and prosecution of the campaign itself. This article analyses the changes in British attitudes and policy towards attacking merchant shipping prior to and throughout the campaign. It then goes on to examine the conduct of the campaign itself and compare it with other British efforts elsewhere during the war. It concludes that the anti-shipping campaign in the Mediterranean was a unique combined arms offensive for the British, and a major evolution in their attitudes and policy towards maritime total war.