When the Sacrosanctum concilium declared that ‘The laity, too, are encouraged to recite the Divine Office, either with the priests, or among themselves, or even individually’ (Sacrosanctum concilium, para. 100), the Church was encouraging the restoration of the Liturgy of the Hours to the place it originally had in the lives of all the faithful. In our earliest Christian text, the Didache, dating from around ce 50, we find that Christians of the first generation were expected to pray the Our Father regularly, three times a day. Thus united in a shared moment of time, even if physically separated, they were praying what later generations came to know as the Liturgy of the Hours, in its most rudimentary form. However, over the next thousand years, the Prayer of the Church gradually became less and less the prayer of all believers and more and more the prayer of the ‘professional’ religious people: priests, monks and nuns. Arnaud Join-Lambert's La Liturgie des heures par tous les baptisés, is a most welcome and impressively thorough study of the place of the divine office in the lives of lay Christians. Lambert looks back to the tridentine reform when the breviary was seen as ‘le compagnon quotidian du prêtre’; his ‘wife’ according to Catherine of Siena (p. 10), and then traces the course of the divine office through the various pontificates of the twentieth century. He describes briefly the pioneers of the Liturgical Movement (Dom Lambert Beauduin, Pius Parsch, Josef Jungmann and their successors) and then discusses the importance given to liturgy generally and to the divine office in particular by Sacrosanctum concilium and subsequent documents issued by the Church's magisterium. He then explores references made to the Liturgy of the Hours in other official documents of the Church: the Code of Canon Law (1983) and the Catechism of the Catholic Church (1992) in particular and also in various allocutions and apostolic letters of John Paul ii. By describing and discussing in some detail various local initiatives in France, Switzerland and Italy, he situates his study firmly in the reality of current church life with all its problems and difficulties. Then in the third section he develops what is his main premise: the theology and the spirituality of the Liturgy of the Hours as a daily sharing in the paschal mystery of Christ and the transforming of time in the passage from day to day, sanctifying the pilgrim journey through life. In this context Lambert shows how the Liturgy of the Hours is a ‘dynamic process’, uniting the believer with Christ in the mystery of his dying and rising relived each day. These various sections add up to an extremely thorough and systematic study which presents the Liturgy of the Hours as a ‘daily experience of the Paschal Mystery’ in the lives of all the faithful. The bibliography too is impressive in its scope of both primary and secondary sources. More and more lay people today are praying the Liturgy of the Hours, or part of it, in some form; Lambert's study is essential reading: a magnificent and comprehensive introduction to and explanation of the recent history, spirituality and theology of the divine office.