The present study contributes to recent renewed interest in the social construction of folk linguistic knowledge and directs its focus to a multilingual workplace. The article reports on an in-depth sociolinguistic investigation in a European institution in Luxembourg. Data were collected in 2020-2021 with trainees and permanent staff in a terminology and communication unit. The data collection triangulated qualitative techniques of longitudinal interviewing, reflective drawing, writing reflection and observation. Analysis of participants' stances uncovered a varying understanding of what multilingualism means in the workplace, how it changes and to what effect. During reflective participation, the trainees heightened their sociopragmatic awareness of diversity in the meaning-making process. Moreover, they ceased to construct their personal multilingualism as proof of professional competence and started to see it as the basis of their own well-being, personal self-realisation and growth. As such, they re-coupled the social and linguistic aspect of their language use and aligned their stances with the permanent staff. This study aims to inspire more innovative approaches with a potential direct effect in multilingual workplaces, especially in those welcoming workers from monolingual or otherwise homogeneous social environments.