Book excerpt: Linguistic variation, loosely defined as the wholesale processes whereby patterns of language structures exhibit divergent distributions within and across languages, has traditionally been the object of research of at least two branches of linguistics: variationist sociolinguistics and linguistic typology. In spite of their similar research agendas, the two approaches have only rarely converged in the description and interpretation of variation. While a number of studies attempting to address at least aspects of this relationship have appeared in recent years, a principled discussion on how the two disciplines may interact has not yet been carried out in a programmatic way. This volume aims to fill this gap and offers a cross-disciplinary venue for discussing the bridging between sociolinguistic and typological research from various angles, with the ultimate goal of laying out the methodological and conceptual foundations of an integrated research agenda for the study of linguistic variation.