The significance of religion in highly modern societies is unmistakable. This raises the question of what the project of secularization actually entails. With both historical and systematic intent, this volume gathers relevant texts on the subject. Advocates and critics of secularization from various disciplines and eras—from Augustine to today's post-secularism—are represented, as well as Christian, Islamic, and Jewish perspectives, along with American concepts that shed particular light on the European secularization discourse. It provides a comprehensive insight into the history and present of a powerful concept.