This book is a detailed study of French-English linguistic borrowing in Prince Edward Island, Canada which argues for the centrality of lexical innovation to grammatical change. Chapters 1-4 present the theoretical and methodological perspectives adopted along with the sociolinguistic history of Acadian French. Chapter 5 outlines the basic features of Acadian French morphosyntax. Chapter 6 provides an overview of the linguistic consequences of language contact in Prince Edward Island. Chapters 7-9 consider three particular cases of grammatical borrowing: the borrowing of the English adverb back and the semantic and syntactic reanalysis it has undergone, the borrowing of a wide range of English prepositions, resulting in dramatic changes in the syntactic behaviour of French prepositions, and the borrowing of English wh-ever words, resulting in the emergence of a new type of free relative. Chapter 10 argues for a theory of grammar contact by which contact-induced grammatical change is mediated by the lexicon.