This volume brings together results from the project “Language and language use among young people in multilingual urban settings” (the SUF project). For the first time, articles by most researchers in the project are published together and in English for an international audience. Many articles contain analyses of various linguistic features of Swedish in the spoken and written data collected from the in total 222 young people participating in the project in the cities of Stockholm, Gothenburg and Malmö. These analyses concern developments in the phonology, syntax and pragmatics in Swedish youth language that have not been described earlier. Other articles use data from the SUF project to explore alternative research approaches and methodologies or to discuss well-established concepts and distinctions within the field of language variation from a critical perspective. Furthermore, some articles deal with multiethnic youth language data from other contexts or with multilingualism on a socio-political level. Taken together, the twelve articles in this volume cover a wide range of aspects of language and language use in multiethnic areas in Sweden, highly relevant for fellow researchers as well as students at different levels of the educational system in Sweden as well as internationally.