Elizabeth Traugott is Professor Emerita of Linguistics and English at Stanford University. Her many publications include Grammaticalization (1993 with Paul Hopper, revised ed. 2003), Regularity in Semantic Change (2002 with Richard Dasher), and Lexicalization and Language Change (2005 with Laurel Brinton).
Graeme Trousdale is senior lecturer in English Language at the University of Edinburgh. His publications include An Introduction to English Sociolinguistics (2010) and The Oxford Handbook of Construction Grammar (2013, co-edited with Thomas Hoffmann).

Elizabeth Closs Traugott and Graeme Trousdale develop an approach to language change based on construction grammar. Construction grammar is a theory of signs construed at the level of the phrase, clause, and complex sentence. Until now it has been mainly synchronic. The authors use it to reconceptualize grammaticalization (the process by which verbs like to have lose semantic content and gain grammatical functions, or word order moves from discourse-prominent to
syntax-prominent), and lexicalization (in which idioms become fixed and complex words simplified). Basing their argument on the notions that language is made up of language-specific form-meaning pairings and that there is a gradient between lexical and grammatical constructions, Professor Traugott and Dr
Trousdale suggest that language change proceeds by micro-steps that involve closely related changes in syntax, morphology, phonology, semantics, pragmatics, and discourse functions. They illustrate their exposition with numerous English examples drawn from Anglo-Saxon times to the present, many of which they discuss in depth.
The book is organized in six chapters. The first outlines the approach and the questions to be addressed. The second reviews usage-based models of language change. The third considers the relation between grammatical constructionalization and grammaticalization. Chapters 4 and 5 focus respectively on lexical constructionalization and the role of context. The final chapter draws the authors' arguments together and outlines prospects for further research. Constructionalization and
Constructional Changes propounds and demonstrates a new and productive approach to historical linguistics.