Linguistic diversity represents a real challenge for a harmonious coexistence in Europe and in today’s globalised world. Language learning has therefore become an undeniable asset of competitiveness in a multilingual European area, with 24 official European Union languages and more than 60 minority languages. This thesis hence focuses on language acquisition during the Erasmus Mundus student mobility program of Euroculture. Does Euroculture succeed in facilitating language learning, thus enabling social integration in the host countries? In order to analyse this issue, it is essential to address English as lingua franca and lingua academica, used in international higher education programs. Some the- ories have been developed on lingua franca and are useful to analyse the role English plays in the Euroculture program. Indeed, Nicholas Ostler’s argument on the end of Eng- lish as lingua franca in the future will be confronted with Louis Jean Calvet’s gravita- tional model of languages. Calvet’s model asserts the predominance of English as lingua franca, which could threaten multilingualism. This is what the study aims to assess. Eu- ropean linguistic policies and tools set up to improve plurilingualism are also explored in order to provide a comprehensive framework and to analyse whether the study findings reflect the recommendations of European policies. An empirical quantitative method con- sisting of 26 questions, submitted to Euroculture students and alumni, has been used to analyse the extent to which Euroculture facilitate language acquisition. The findings have shown that two main factors facilitate plurilingualism: the language courses offered at partner universities and students’ own decisions to integrate in the host countries through various factors are among the elements facilitating language acquisition. The research also revealed important barriers in the language learning process and the social integra- tion in host countries, namely the “Euroculture bubble” phenomenon, the predominance of English as lingua franca and barriers to access language courses.