This article addresses key issues related to diverse cases of migration to complex multilingual environments within Europe. Data came from three case studies carried out within the scope of the MIME project: (ex-)Yugoslavian refugees to South Tyrol (Italy); Portuguese work migrants to Andorra; and international managers in Vasa (Finland). Data were elicited using qualitative methods (biographical narrative interviews and focus groups) and thematically analysed to identify emic causes of 'linguistic unease', the speakers' perception that their linguistic repertoire is inadequate for communicating with others and the consequent fear that their linguistic performance will be met with judgemental and negative attitudes. Our results show that in all situations, irrespective of the diverse conditions that exist prior to migration or in the destination country, the complex linguistic environment of the recipient society is puzzling for mobile people. In all cases, numerous migrants target the language that they perceive to be easier and most accessible to them, but this also exposes them to some level of linguistic unease. Crucially, migrants' learning choices rub salt in the wounds of old conflicts that have roots in the historical dynamics of multilingualism of the recipient societies. We argue that raising sociolinguistic awareness about this is crucial to mitigate unease and discrimination in the most vulnerable sections of the migrant population.