The chapters in this volume, grouped into three thematic parts, present a broadpicture of the diversity of multilingual cities across the world in the 21st century.They explore cities of vastly different size, ranging from megacities such as Ja-karta down to small cities such as Fribourg/Freiburg, and cities situated in theGlobal North as well as in the Global South. The dynamics of and interaction be-tween different languages in those cities also demonstrate great variation, fromthe presence of two or more languages in multilingual countries or regions to thestatus of immigrant languages in cities traditionally dominated by one majoritylanguage, and to post-colonial contexts where colonial languages often co-exist asofficial languages alongside indigenous languages. While national varieties of En-glish, as well as English as a lingua franca, play an important role in the languagemake-up of many of the cities analysed in this volume, in others the focus is onother (originally) European and non-European languages. As a result, the specificcircumstances of each of the cities sometimes demand different methodologicalapproaches to do them justice, while other chapters share a common methodolog-ical approach to document multilingualism in the cityscape. This is the case withfive chapters (identified in turn further below) across all three sections which uselinguistic landscaping as their approach, carefully fine-tuning the methodology soas to fit the particular conditions of each site.