There is already an important literature on religion and political philosophy, focusing especially on controversies about religious symbols, freedom of speech, or secular education. The introduction explains the distinctive approach of the volume. Instead of focusing on specific political controversies, the book explores the conceptual, structural architecture of liberal political philosophy itself. The authors distinguish four different themes: the special status of religion in the law; state sovereignty, non-establishment, and neutrality; accommodation and religious freedom; and toleration, conscience, and identity. The chapter explains the particular questions raised in each of these four themes, and briefly presents the twenty-two contributions gathered in the volume.