In what is essentially an intellectual history of English religious dissent from Wyclif to the eve of the Reformation, Patrick Hornbeck grapples with what have become major questions for the historian of heterodoxy in late medieval England: what was ‘Lollardy’ and does it remain a useful term? Hornbeck concludes that it does, albeit with a de rigueur lower case ‘l’ that resists false notions of coherence and intellectual lineage that were largely the creation of Protestant polemic. This book is important for two reasons. First, because it proposes a new methodological model for the study of lollardy and, second, because it provides a comprehensive synthesis and survey of English heterodox beliefs in a number of key doctrinal areas. The model that Hornbeck applies is that of ‘family resemblance’ or polythetic classification, which is derived from Wittgenstein. Instead of seeking to establish a set of criteria which all possible lollards must adhere to in order to be true lollards, the ‘family resemblance’ model looks for the similarities between different sets of beliefs held by different individuals or contained in different texts. Any two individual lollards or lollard texts will always share some beliefs but there is no defined set of necessary or sufficient beliefs that make them ‘lollard’. Rather, they are related in some meaningful way and their relationship with other lollard individuals or lollard texts will be different, sometimes markedly so, but they will nevertheless bear some resemblance. Hornbeck applies this model to five doctrinal categories: salvation, the eucharist, lay marriage and clerical celibacy, priesthood, and the papacy. In each case he sets out an impressively comprehensive and clear sighted account of Wyclif's own position, those found in Wycliffite texts, the recorded beliefs of heresy trial suspects and those imputed to so-called heretics by anti-Wycliffite polemicists and the ecclesiastical hierarchy. The Wyclif/Wycliffite/lollard ‘family resemblance’ displayed a remarkable degree of heterogeneity but a loosely shared network of particular heterodox ideas and vocabularies is clearly recognisable. So, for example, lollards, unlike Wyclif, tended to hold to a works-oriented position on salvation whilst adopting his vocabulary of predestination, perhaps because of the influence of orthodox religious culture. In other areas the similarities were greater between academic Wycliffism and lollardy. For example, there was a surprising continuity of moderation on issues such as the priesthood and the papacy, despite the more extreme statements of Wycliffite and anti-Wycliffite polemicists. Chronology was important but lollard rationalities did not always decline in subtlety over time as they moved from Latin into English and popular speech. Geography, the influence of individual local leaders and of particular heterodox texts were also important factors in creating different doctrinal positions amongst ostensibly unconnected networks. Given Hornbeck's theoretical starting-point it is arguably somewhat counter-productive to offer a list of eight ‘markers of lollard affiliation’ (p. 197) in the concluding chapter. More helpful is the discussion of the dynamics of the development of heterodoxy and how they may have differed from orthodoxy. Hornbeck includes the social connections between dissenters and the effects of persecution in his list of ‘markers’ and rightly calls for the integration of doctrinal approaches with those that explore the social, political and psychological aspects of dissent. This study makes a valuable contribution to that endeavour.