There are various studies investigating the speech community of people of German descent from Russia (Russlanddeutsche) and their language use. This study found various language contact phenomena, most remarkably code-switching. It examines how the Russlanddeutsche alter their speech according to its possible functions in discourse. Thus, this qualitative study focuses on the morpho-syntactic and interactional linguistic analyses of spoken data in natural contexts and situations. In order to thoroughly answer the complex question ‘How do speakers use the languages available to them?’ This study takes the following socio-cultural factors into account: the sociolinguistic aspects of the interlocutors taken from their biographies, especially information about the preferred language of the speakers etc.