No member of the Society of Architectural Historians needs to be told that The History of the King’s Works is a monument of twentieth-century scholarship, founded on research so prodigious that the editor himself, in his preface to the only volume in which he took no specific part, warns us that ‘no one . . . who has not worked long hours in the Public Record Office can fully appreciate the sustained endeavour that lies behind the writing’: those for whom the thought of mere mornings in those gloomy search-rooms is daunting can only be humble in the face of such depth of documentation. Moreover the documentation within these magisterial volumes is itself fully enabling: Mr Colvin and his colleagues have done the research for us — done it, it is impossible to question, with terrifying thoroughness — but left all their stages visible for any reader to retrace. Though, as Mr Colvin concedes, ‘it would be sanguine to suppose that no relevant document has escaped [the authors’] scrutiny’, it is certain that the documentary survey is as complete as human endeavour can make it. In one very important respect, though the History incorporates in many cases recent archaeological research, the buildings themselves have been explored less exhaustively; and it is not quite enough, if one is proposing a total enquiry into what can be known of the King’s Works, to excuse oneself from the study of (especially medieval) technology by referring readers to Salzman. In the third of a century since Building in England was published (itself an exemplary, not an exhaustive, book) much has been learnt about medieval building construction; and some is surely inferable from documents studied for The History of the King’s Works and from the buildings themselves: the characteristically empirical approach of medieval builders to structural problems led to individual solutions which one would like to learn about. How, for instance, were the special difficulties of founding Conway Castle on its precipitous and very uneven rocky site overcome? There is no-one better-equipped to tell us than Dr Taylor; but he is silent. The series aimed to write ‘the history of the government department long known as the Office of the King’s Works, and of the building operations for which that office was responsible’: the process of building is at least as interesting and important as where the money or the stone came from, or how long the surveyors or workmen waited to be paid.