R.H. Tawney is an iconic thinker in British left-wing circles, whose writings during the early-mid 20th century helped to forge the direction of democratic socialist thinking and Labour Party policies. This book provides a fresh and accessible guide to the ideas of Tawney for new readers and to set straight the record of what Tawney's political thought really is, warts and all, in place of the rather over-simplified picture painted by the major commentators. It shows how Tawney's ideas changed over nearly 40 years of writing, as his own life experiences and the traumatic events of the two World Wars and their aftermaths drew him to a more secular and practical interpretation of politics. The book renders a service to scholarship, being based on original research, including examination of the Tawney Archive at the LSE, and makes use of unpublished works of Tawney.