Part I. Understanding Secularization: 1. The secularization debate; 2. Measuring secularization; 3. Comparing secularization worldwide; Part II. Case Studies of Religion and Politics: 4. The puzzle of secularization in the United States and Western Europe; 5. A religious revival in post-communist Europe?; 6. Religion and politics in the Muslim world; Part III. The Consequences of Secularization: 7. Religion, the Protestant ethic, and moral values; 8. Religious organizations and social capital; 9. Religious parties and electoral behavior; Part IV. Conclusions: 10. Secularization and its consequences; 11. Re-examining the theory of existential security; 12. Re-examining evidence for the security thesis.