The origins of this book lie in the study of the French Socialist Party which I undertook as a postgraduate student at St Antony's College, Oxford, under the able direction of Mr Philip Williams. It was also my good fortune to have as a neighbour in Winchester Road Dr Saul Rose, Fellow of St Antony's, who had previously been the International Secretary of the Labour Party and whose work with the French Socialists had given him a sensitive understanding of their outlook and their characteristics as a party. Both then and later he was unfailingly generous with help and advice and he remained an intellectual stimulus and good friend until his untimely death in 1992.

My initial research was carried out between 1958 and 1962, first at St Antony's College and then as a member of the Cycle Supérieur d'Etudes Politiques at the Fondation Nationale des Sciences Politiques in Paris, where I received invaluable advice from Professor René Rémond, M. Serge Hurtig and M. Jean Touchard. At the time I was mainly concerned with the Socialist Party's involvement in tripartisme at the levels of parliament and government, but I became increasingly aware of the readiness of the Socialists of the post-war period to compare the internal difficulties which they were experiencing with those which had beset the party in 1938.