This book introduces the life and thought of two British contemporaries who were decisive in shaping the modern ecumenical movement: the Scottish layman J. H. (Joe) Oldham (1874-1969) and the Anglican bishop G. K. A. (George) Bell (1883-1958). Their careers were rather different but closely related. Oldham was a missionary statesman, the organizing secretary of the 1910 Edinburgh World Missionary Conference, and a pioneering thinker and writer on race and social ethics who set the agenda for the crucial ecumenical conference on Church, Community, and State at Oxford in 1937. A quiet, skillful diplomat, he was the decisive mind behind the formation of the World Council of Churches (WCC). Bell was the public, prophetic voice of the ecumenical fellowship from the 1930s onward, steadfastly leading the churches' support for the Christian opposition to Hitler in Germany, tirelessly working for refugees and all victims of oppression, and after the war pioneering the work of reconciliation. After the inauguration of the World Council of Churches in 1948, he served as the first chairman of its central committee. It was widely believed that he would have become Archbishop of Canterbury but for his courageous and outspoken opposition to the British and American policy of bombing civilian populations during the war. The book outlines the life and main engagements of each figure in turn, and then provides a selection of their key writings to illustrate their thinking and their impact on ecumenism. A final chapter reflects on their pioneering significance and their relevance today.