This thesis attempts to give an account of how Whitehall planned Britain's withdrawal from extra-European commitments in the years 1959-1968, demonstrating that foreign policy development was essentially a cross-departmental process, involving a synthesis of views articulated by the Treasury, Board of Trade, Ministry of Defence, Colonial Office, Commonwealth Relations Office, as well as the Foreign Office. More specifically, the thesis is concerned with the direct effects of the interplay of different departmental policies on British retrenchment from Africa, the Middle East, and the Far East. Most accounts of how ministers and officials approached the subject of withdrawal from international commitments lack any substantive analysis of documentary evidence, a fact attributable to the 'thirty-year rule'. Many academic works also contain a reference to 'delusions of grandeur' as the main explanation as to why Whitehall guided a tentative course in extracting Britain from its remaining overseas obligations. By examining Whitehall's attempts to review future policy, usually on an inter-departmental basis, this thesis questions the commonly held assumption that an outdated imperial sentiment permeated the political establishment until economic reality, namely the devaluation of sterling in November 1967, forced Britain to confront the fragility of its position. Developing and expanding upon previous scholarship, this thesis makes a contribution to historical knowledge by providing the first sustained and unified study of how the highest echelons of Whitehall framed Britain's long-term strategic aims in the late 1950s and 1960s. This thesis is a contribution to administrative, diplomatic and military history, and provokes a number of questions. To what extent, for example, did economic considerations inform the decisions of leading policy-makers? Did a misjudgment over the strength of British 'power' lead to the pursuit of inappropriate foreign policy objectives? How was foreign policy affected by defence policy? What influence did the Treasury exert over high foreign policy? Did the influence of civil servants vary according to policy issues and the personalities involved? In what ways did the views of the departments responsible for economic matters differ from those in charge of defence policy on the priority attached to military expenditure? To what extent did the Foreign Office and Ministry of Defence disagree on matters regarding Britain's overseas commitments and possessions? In answering such questions, this thesis casts new light on how Whitehall, between 1959 and 1968, reduced the scope of Britain's international commitments, redirecting the central thrust of British foreign policy away from extra-European commitments towards Europe.