Аннотация:This chapter focuses on the linguistic aspects of the internal migration to Moscow from other regions of the Russian Federation. We explore the functions of languages other than Russian in the Moscow region and identify factors of language vitality in urban settings. We also compare the situation in the Moscow region with the general linguistic situation in particular regions of Russia. The main source of the data on functions and evaluation of minor languages was a collected corpus of sociolinguistic interviews of bilingual and multilingual Russian citizens residing in Moscow for a long time or permanently.