Ronald Inglehart traces the global decline of religion using the World Values Surveys and the European Values Surveys, which impressively contain representative data from 112 countries and territories collected over the past 40 years. While many of the findings and ideas have appeared in previous publications, this new book stresses a 'sudden decline' during the past decade in the number of people indicating that God is 'important' to their lives. Inglehart hypothesizes that religious decline is the result of increased existential security due to advances in medicine, technology, and resource abundance. Existential security produces 'individual-choice norms' which, in turn, undermine 'pro-fertility' norms; consequently, cultural shifts concerning the norms of reproduction, sex, marriage, and family structure map onto a decline in traditional religions which tend to advocate anachronistic rules concerning social sexual behavior. His model of secularization is clean and fits the data presented, although critics have questioned his narrow definition of what constitutes religiosity. Most interestingly, in the final chapters Inglehart begins to intimate that this secularization trend is not necessarily permanent. For instance, climate change, global pandemics, and anti-democratic movements all undermine the existential security felt in wealthy democratic countries. Will these dangers lead individuals to seek out the sanctuary of religious belief and communal worship as modern societies grapple with their own tenuous hold on social order and safety? Ingelhart does not predict a return to a religious past but does identify backlashes to secularization. The 'secularization debate' is far from over, but Ingelhart's latest contribution establishes certain facts about religious decline and posits some logical sources for why many citizens in the post-industrial world are losing their religion.