This is the first volume published in English of a series of International Handbooks of Catholic Theology under the general editorship of Cardinal Christoph Schönborn, Archbishop of Vienna.The book is a comprehensive introduction to the liturgy of the Roman Rite, set within a broader consideration of Christian liturgies Eastern and Western (Byzantine, Mozarabic, Ambrosian, and Reformed). The central theme of the book is the life-creating communication between God and human beings. Part 1 deals with God's invitation to humanity to enter the divine fullness of life. This is God's descent or "katabasis." Part II is concerned with humanity's acceptance of the invitation—the human ascent to God or "anabasis." Following this extensive treatment of the general nature of Christian liturgy are four sections devoted to particular subjects: the celebration of the Eucharist, the celebration of the sacraments, the liturgy of the hours and other services of the Word, and, finally, the liturgical year.