The aim of this book is to investigate and attain new insights on how and to what extent the wider sociolinguistic context of language use and contact impinges on formal grammatical structures. The papers contained in the book approach this important problem from various points of view by focusing on language evolution and change, on multilingualism, language mixing and dialect variation, on spoken language, and on creole languages. Given the theoretical perspectives, methodological focus, and analyses, the book will be of interest to theoretical linguists as well as sociolinguists, from undergraduate students to researchers.