Historically, what did the Church and theologians mean by apostolicity, apostolic tradition, apostolic churches, and apostolic succession? Theologically, what have important postconciliar theologians taught about apostolicity? How have world views shaped the understanding of apostolicity? How might the thesis of the apostolicity of the whole Church impact other ecclesiological and sacramental issues? Ecumenically, what are the points of agreement in several important ecumenical dialogues? Which points are disputed among the churches? Apostolicity Then and Now addresses these concerns.