Although Parliament is the principal source of authority in the British political system, it is the Cabinet which stands at the pinnacle of government. Yet what actually happens at Cabinet meetings? How are decisions made, particularly in the arena of foreign policy? Such questions have hitherto been largely overlooked by both historians and political scientists. In this book, Dr Christopher Hill presents a detailed case-study of the British government and foreign policy, during the dramatic period from the Munich Conference of 1938 to the German invasion of the Soviet Union three years later. Using extensive archival material, he examines how far the strong personalities of Neville Chamberlain and Winston Churchill respectively were really able to dominate their Cabinets in an area of policy where Prime Ministers have traditionally been supposed to exercise considerable freedom. This analysis concentrates on six decisions that were of key importance in committing Britain to the war which began in September 1939 but which changed so sharply in character in June 1940 with the fall of France. An original study of foreign policymaking at the highest level, this book will be widely read by international relations specialists while historians will welcome the close-textured account of key episodes of this period. It will also reinvigorate debates among political scientists on the nature of Cabinet government.