For at least two decades there has been a profusion of applied linguistics research on academic writing, inspired either by an interest in its language features or a quest for pedagogical effectiveness. A key issue is the identification of the grammatical and rhetorical complexity in academic discourse, as we can see in a wealth of influential works (e.g. Halliday and Martin 1993; Hyland 2004; Biber 2006). Little attention, however, has been given to diachronic changes in the language of academic writing. Thus Grammatical Complexity in Academic English: Linguistic Change in Writing is valuable reading for those applied linguists who are concerned with academic writing, discourse analysis, and changes in language over time. Based on large-scale corpus analysis, this book challenges stereotypical views about the grammatical complexity of academic writing, and its main theme is phrasal complexity and the discourse functions associated with it. From a synchronic perspective, the authors demonstrate how ‘academic written registers are unlike other registers in their reliance on phrasal complexity features rather than a clausal style of discourse’; from a diachronic perspective, more importantly, their study documents ‘linguistic innovations that have emerged in writing, especially science research writing’ (p. 39). Seven chapters revolve around this running theme. In Chapter 1, by problematizing the dominant stereotypes and assumptions of academic writing, the authors introduce the primary focus of their study. Chapter 2 spells out the corpus-based approach to linguistic analysis, as well as the specific corpora and analytical methods used in the study. Chapters 3–6 present the major findings of the research, with Chapters 3 and 4 on quantitative corpus findings, while Chapters 5 and 6 present more interpretive linguistic analyses. Chapter 7 summarizes the authors’ argument, leading into a discussion of applied implications.