Existentialism was one of the most important influences on 20th century thought, especially in the period between the 1920s and early 1960s. Best known in its atheistic representatives such as Sartre, it also numbered many significant religious thinkers. This text is a critical introduction to these religious existentialists, who are treated as a coherent group in their own right and not merely derivative of secular existentialism. The book argues that they constitute a distinctive religious voice that continues to merit attention in an era of postmodernity.