More detailed than preceding social encyclicals, Pope Benedict XVI’s Caritas in veritate appears to supply a theological foundation for the Catholic Church’s social doctrine. The article argues that the theological anthropology contained in the encyclical (which leads to a notable revaluation of the role of grace) complements Joseph Ratzinger’s life-long reflections on the relationship between faith and reason, and provides a key to understanding choices the pope makes in his effort to offer a reliable Catholic orientation in a rapidly changing world.