This unique and comprehensive study outlines, clarifies, and defends the official Roman Catholic teaching on the relationship between Christianity and other religious traditions in the light of the Catholic belief that “We must hold that the Holy Spirit offers to all the possibility of being made partners in a way known to God, in the paschal mystery” (Gaudium et Spes, 22). Part I studies the history of these issues while Part II examines their theological framing. Part III addresses Christianity and other religions since Vatican II. Part IV deals specifically with Judaism, Confucianism, Hinduism and Islam as these religions see themselves in relation to Christianity. A final chapter by Bishop Michael Fitzgerald offers a theological reflection on the foundations of inter-religious dialogue today.