The study of language variation from a geographical perspective has become the subject of renewed interest thanks to new theoretical, empirical and technological developments, such as advances in the study of language and dialect contact, the creation of new dialectal corpora or the availability of computer tools to create maps from geolocated linguistic data. The present volume features research that takes advantage of these developments and brings together the efforts of linguists working in historical linguistics, sociolinguistics, dialectology, corpus linguistics and computational linguistics in exploring the diffusion of language changes in the physical space.