During the Middle Ages, the Divine Office, or daily round of prayers, formed the central focus of the monastic life. The liturgical book which contained all the prayers, hymns, etc. which were said at each office during the year is the breviary. The present volume is widely acknowledged as the best introduction available in English to the complex structure of the Office. Initially the Benedictine Office is considered, followed by an assessment of the numerous additions and alterations which occured during the early medieval period. To conclude there is a detailed discussion of the structure of various individual offices in late medieval England as they are known from surviving breviaries. Throughout, the language has been kept plain and non-technical to make it accessible to all students of the middle ages.