The problem of change has assumed great prominence in much of the current ferment in theology, and many of the issues in question can best be interpreted as relating to the validity and limits of doctrinal development. The questions cannot be faced constructively, however, until the development of doctrine has been clearly charted, a historical as well as a theological assignment. In this unique introductory survey--more modest in scope but more scholarly in method than Cardinal Newman's great programmatic essay of 1845--Mr. Pelikan presents three case histories of the particular doctrines that have crucial points of division among Christians. His cogent analyses of Cyprian on Original Sin, Athanasius on the Virgin Mary, and Hilary on the Holy Spirit demonstrate the interaction between the sacramental life of the Church and the intellectual work of the theologian that consistently marked the development of doctrine by the early Fathers. Thus they clarify some central aspects of the continuing theological and ecumenical debates. Mr. Pelikan, Titus Street Professor of Ecclesiastical History at Yale University, is the author of many books and articles, including a forthcoming full-scale history of the development of doctrine.