This monumental two-volume publication brings together in the original languages and an English translation, all the decrees of all the ecumenical councils from Nicaea I to Vatican II. As such it represents an indispensable reference work for theologians and historians, as well as for anyone interested in the development of Christian thought and doctrine. Indeed, these decrees represent the authoritative distillation of Christian tradition which itself is bound together with scripture "in a close and reciprocal relationship" so that the two "form a single sacred deposit of the word of God, entrusted to the church."

The original text is a reproduction of the brilliant edition by G. Alberigo and others of the decrees Conciliorum Oecumenicorum Decreta, which provides for the first time a reliable critical text for all the ecumenical councils. The English translation faces each page of the original text and is the first rendering into English of all these decrees taken together. The translators have used inclusive language throughout to emphasize the continuity of conciliar documents.

The 2,528 total pages of these two volumes include all the authenticated texts and their English renderings as well as a preface and introduction by the oringinal languages editor, a foreword by the English language editor, a bibliography for each decree, various commentaries and explanatory notes, and ten comprehensive indices.