Calvin's doctrine of the Church is crucial to his theology. But, as Richard Muller notes, Calvin's ecclesiology ‘has received comparatively less attention than other doctrinal topics’ (p. ix). This makes Maruyama's work most welcomed. This veteran Reformation scholar treats Calvin's views chronologically through the Reformer's ‘Academic formation and Catholic ecclesiology’; to ‘The early Genevan reformation and practice of Catholic ecclesiology’; on to ‘The Strassbourg period and a transition to new rcclesiologies’ and finally, ‘Reformed ecclesiology and Reformation ecclesiology’. By ‘Reformed ecclesiology’, Maruyama means ‘Calvin's Reformed ecclesiology’, which he had formulated in consultation with, as well as in distinction from, other Evangelical Reformers’ (p. 379). Maruyama sees the third edition of Calvin's Institutes (1543) as ‘the most important edition for understanding Calvin's concept of the church's form’ (p. 379). Also important was Calvin's First Corinthians commentary (1546). Maruyama agrees with Doumergue's assertion about the importance of the 1543 edition for Calvin's ecclesiology: ‘after 1543 it is finished; 1559 adds nothing’ (p. 380). 1543 materials are almost ‘completely carried over into the final edition [1559 – Latin; 1560 – French] in a more easily understood expression, it occupies ten chapters (chs iii-xii), just about one half of book iv of the 1559 Institutes’ (p. 381). Maruyama characterises the addition as representing ‘what is generally described as church government or polity’. The ‘main thrust of all its arguments is the sharp contrast between church government based upon scriptural norm and that of the papal church’ (p. 381). Maruyama insists that ‘Reformation ecclesiology’ is ‘not a theological but a historical concept’. It was an attempt to conceive ‘salvation history in the church of the Reformation era’ (p. 401). It is true that ‘the theological framework of the so-called ‘Calvin's ecclesiology’ in book iv of the 1559 Institutes defined his Reformation ecclesiology. Yet, Reformation ecclesiology as a historical concept indicates his understanding of the entire Church and its reform from Luther's time to his own’. Calvin's aim was ‘to place his own idea of the Evangelical church and its reform in that frame’ (p. 401). In his 1559 Institutes with its book iv titled: ‘The external means or aids by which God invites us into the society of Christ and holds us therein’, Maruyama indicates ‘Calvin had recognised “an urgent need for formulating” the external “form” of the Evangelical Churches that would be able to counter the Roman Catholic hierarchy’ (p. 443). Maruyama's thorough historical study of the impact of the early Reformation context on Calvin and his shaping of a Reformed ecclesiology is an important contribution to our understandings of Calvin's views on the Church and how they developed.