Professor Mustajoki’s research has encompassed Russian functional syntax, corpus linguistics, intercultural pragmatics, and the sociolinguistics of Russian as a pluricentric language, with particular attention to the mechanisms and causes of miscommunication in everyday and lingua-franca interaction. He has also played a formative role in developing the institutional infrastructure for Russian and East European studies in Finland, contributing to the establishment of the Slavonic Library and the Aleksanteri Institute at the University of Helsinki, as well as major scholarly journals including Studia Russica Helsingiensia et Tartuensia and Idäntutkimus (Eastern Studies). His scholarly contributions include a comprehensive monograph on Russian functional syntax and influential studies of Russian modernisation and the international role of the Russian language, including works published by Routledge and John Benjamins. His selected publications address metonymical conceptualisation and personification in corpus analysis, the democratisation of Russian, miscommunication in everyday and lingua-franca interaction, the preconditions for Russian modernisation, and functional approaches to Russian syntax. Collectively, these contributions reflect a sustained research programme connecting rigorous linguistic analysis with the cultural, social, and political dimensions of Russian in contemporary international society.