Religion remains an important influence in the world today, yet the social sciences are still not adequately equipped to understand and explain it. This book advances an innovative theory of religion that goes beyond the problematic theoretical paradigms of the past. Drawing on the philosophy of critical realism and personalist social theory, Christian Smith explores why humans are religious in the first place—uniquely so as a species—and offers an account of secularization and religious innovation and persistence that breaks the logjam in which religious scholarship has been stuck for so long. Certain to stimulate debate and inspire promising new avenues of scholarship, Religion features a wealth of illustrations and examples that help to make its concepts accessible to readers. This superbly written book brings sound theoretical thinking to a perennially thorny subject, and a new vitality and focus to its study.