This paper investigates multilingualism as language and communication discourses and practices in a Copenhagen metro tunnel construction project. This project is characterised by transience: continual time-space changes of work organisation and staff relations combined. In this scenario, a highly international and multilingual staff composition puts focus on language and communication. Based on interviews with managers and workers from one of the project’s contractors, as well as observations of daily work in the tunnels, the analysis demonstrates participants’ discursive constructions of language and communication, sometimes linking these concepts to work, sometimes to relationship-building. I argue that these constructions are closely interlinked with the workplace’s transient status and conditions, and draw out how they have empowering as well as exploitative implications for the workers.