The extant works of Saint Augustine comprise a vast corpus of five million words, one of the most extensive body of writings of any author. From November 12 to 14, 2019, scholars, students, and activists from North Africa, Europe, and the United States gathered in Carthage, Tunisia. They met in the city where Saint Augustine once studied and taught to explore the relevance of his thought for the twenty-first century. Reaching across religious, philosophical, and cultural differences, they examined components of a new humanism required to confront the global challenges the world faces. Together, they imagined an aggiornamento of shared spiritual values needed to meet the levels of self-sacrifice and international cooperation required by the challenges of the times. In The Relevance of Saint Augustine for Twenty-First-Century Global Challenges, editor Joseph T. Kelley presents a collection of the papers delivered at the conference. It brings Augustinian thought into interreligious dialogue on the international scene.