The defeat of 1940 and its aftermath stimulated a wide-ranging debate in France about the causes of national decline and the possible sources of renewal. During the period between 1940 and 1946, and in particular in the two years after the liberation in 1944, most of the nation's political, social and economic structures were re-examined. A multitude of plans and programmes were elaborated with a view to carrying through significant reforms after the war had ended. The aim of this dissertation is to review the process of rethinking. Its major focus is on the ideas of national political elites, although it also attempts, wherever possible, to draw on sources nearer the grass roots. The dissertation is divided into two parts. The first part considers the postwar plans formulated, in the months around the Liberation, by the new elites of 1944: the Resistance movements, the Free France organisation, General de Gaulle, and the three dominant political parties (the Communist party, the Socialist party, and the Christian Democratic M.R.P.). These chapters deal, in general terms, with the reformist ideologies of the above groups, and also, in particular, with the ways in which they approached the problems of planning for the postwar period. A second group of chapters examines the rethinking in a thematic sense. This part traces the development of reformist ideas on a number of the issues which were identified as particularly crucial to a future national recovery: the political and constitutional regime; the form of the French empire and its relation to the <i>metropole</i>; the structures of the French economy; and the problems of French society (specifically, of the educational system and of relations between labour and capital). A thematic approach places the views of the national political leaders in a broader context by including the ideas of civil servants, intellectuals, pamphleteers, and other non-political figures. It also permits some observations about the political vocabulary of renewal - a vocabulary which reflected both consensus and ambiguity.