Keith Clements draws on important hitherto unexplored archival material. Sections relate to Oldham's time as a missionary in India, his role as Secretary of the World Missionary Conference, usually recognised as the birth of the modern ecumenical movement, his reconciliatory roles in the First and Second World Wars, and his involvement with the 'Life and Work' movement. In a final chapter Dr Clements reflects on Oldham's considerable and continuing relevance today.