The book’s focus on contemporary urban settings sheds light on the new language practices and mixed ways of speaking resulting from large-scale migration and the intense contact that occurs between new and existing languages and dialects in these contexts. In comparing these new patterns of language variation and change between cities in both Africa and Europe, the volume affords us a unique opportunity to examine commonalities in linguistic phenomena as well as sociolinguistic differences in societally multilingual settings and settings dominated by a strong monolingual habitus. These comparisons are reinforced by a consistent chapter structure, with each chapter presenting the linguistic and social context of the region, information on available data (including corpora), sociolinguistic and structural findings, a discussion of the status of the urban contact dialect, and its stability over time. The discussion in the book is further enriched by short commentaries from researchers contributing different theoretical and geographical perspectives. Taken as a whole, the book offers new insights into migration-based linguistic diversity and patterns of language variation and change, making this ideal reading for students and scholars in general linguistics and language structure, sociolinguistics, creole studies, diachronic linguistics, language acquisition, anthropological linguistics, language education and discourse analysis.