What can people do with multiple languages that they cannot do with one? What kinds of practices does multilingualism enable and how does it shape communication in the digital sphere among young people? These questions have motivated the volume Multilingual Youth Practices in Computer-Mediated Communication (CMC). This volume was inspired by some of the work now emerging in sociolinguistics on the multilingual digital practices of people in a globalizing world (e.g. Androutsopoulos 2015; Barton & Lee 2013; Danet & Herring 2007a; Deumert 2014a; Spilioti & Georgakopoulou 2015; Jones et al. 2015; Lee 2017; Thurlow & Mroczek 2011a). In contrast with these volumes, however, the present work aims a spotlight the multilingual practices of young people who have taken up the affordances of digital communication more fervently than any other age group (Beheshti & Large 2013; Buckingham & Willett 2013). More specifically, we examine how the "digital generation" in different parts of the world makes use of multilingual repertoires and the social meanings they attach to various linguistic features in their digital communications with others