This book attempts to outline a theology of the Church for the twenty-first century. Starting from a principle that was enunciated in Paul VI's first encyclical (Ecclesiam suam), it finds its focus in the awareness of being the Church that is implied in the profession of the Christian faith. It takes full account of the contemporary manner of reading Scripture, and it sees the tradition as an unfinished forward movement. The ecumenical dialogues and the encounter with religions that were the fruits of Vatican Council II contribute to the discussion. The future of the Church is anticipated in light of scientific findings regarding the shape and history of the universe. This ecclesiology is profoundly Cathohlic, experiential, and Trinitarian.