The Eucharistic Prayer is the most central and distinctive form of Christian public prayer apart from the Lord's Prayer itself. It gradually evolved into fixed forms during the early Christian centuries, and the Eucharistic Prayer of Addai and Mari is almost certainly the oldest such prayer still in regular use.Dr Gelston's study presents a critical edition of the medieval Syriac text of this ancient Eucharistic Prayer. The text, which is eclectic, is accompanied by a select critical apparatus and a translation, and is followed by textual notes on the variants in the apparatus. The detailed commentary, accessible to those who do not read Syriac, is concerned chiefly with literary-critical and historical questions such as the parallels with the Maronite anaphora Sharar which provide a particular opportunity to detect possible later accretions and modifications. A tentative reconstruction of the Prayer as it may have been at about the beginning of the fifth century is offered in an appendix, and an introduction sets the Prayer in its wider context.