This paper is grounded in the evolution of our reflection on the relationship between plurilingualism, plurilingual speech and language learning. That is, it refers to research on the construction of plurilingual repertoires, over a period of more than thirty years, as documented in Lüdi and Py (1986 [2009]. "To Be or Not to Be … a Plurilingual Speaker." "International Journal of Multilingualism" 6 (2): 154-167; [2013]. "Etre bilingue. 4e édition ajoutée d'une postface." New York: Lang) and Lüdi et al. ([2016]. Managing Plurilingual and Intercultural Practices in the Workplace. The Case of Multilingual Switzerland. Amsterdam: John Benjamins), among others. The emphasis is placed on language use (languaging) instead of on language systems (language), based on the premise that plurilingual competences emerge from interaction where the status of translinguistic markers is mutually negotiated. In this context, the question of the adequacy of 'additive' or 'integrated' conceptions of plurilingualism constitutes an important theoretical challenge.