This special issue brings together research at the intersection of two emerging areas of scholarship in sociocultural linguistics, digital communication and superdiversity. It explores this relationship from two angles: the role of digital language practices in contexts of societal superdiversity, and the relevance of superdiversity as a theoretical perspective for the study of digital language practices. The detailed empirical analyses of the nine papers in the issue show that digital language practices in settings of superdiversity extend and complicate the semiotic resources available to people or their performance of identities and social relationships.