The aim of this paper is to contribute to the understanding of the role of language in multilingual blue-collar workplaces by investigating how communication is realized in construction sites in Qatar. The State of Qatar offers a unique and, hence, very interesting setting for the linguistic investigation of migration-related issues, such as multilingualism (Pietikäinen et al. in Sociolinguistics from the periphery: small languages in new circumstances, Cambridge University Press, Cambridge, 2016), due to the fact that over 90% of its population consists of non-citizens (Ahmad, in: Kamrava, Babar (eds) Migrant labor in the Persian Gulf, Hurst & Company, London, pp 21-40, 2015). In addition, after its successful bid to host the World Cup 2022, the country is currently witnessing a rapid transformation of its landscape evident through its massive number of construction sites, where people of different national, ethnic and social class backgrounds from all over the world are hired to work together in developing the infrastructure that is part of the ambitious Qatar Vision 2030. Against this backdrop, the focus is on the sociolinguistic resources (Blommaert in The sociolinguistics of globalization, Cambridge University Press, Cambridge, 2010) mobilized in a construction site at a university in Qatar. The multilingual community of practice (Lave and Wenger in Situated learning: legitimate peripheral participation, Cambridge University Press, New York, 1991) investigated consists of blue-collar workers from India and their communication practices with their supervisors, who are project site engineers from all over the world. In such transnational fields, where effective communication is a sine qua non not only for the successful completion of the project or infrastructure itself but also, and perhaps most importantly, for the safety of everybody involved in the construction, multilingualism is the norm. It is argued that communication is realized through spatial repertoires (Canagarajah, in: Canagarajah (ed) The Routledge handbook of migration and language, Routledge, New York, pp 1--28, 2017), that are constructed and used as ingroup markers to facilitate communication among people from different nationalities, ethnicities and social classes. The ethnographic data, collected for almost 13 months, comprise voice-recorded interactions, field notes from on-site participant observation as well as ethnographic interviews with select blue-collar workers and their supervisors. The linguistic and exolinguistic analysis is contextualized in the broader socio-political and economic forces of Qatar (Fromherz in Qatar. A modern history, Georgetown University Press, Washington, 2012; Kamrava in Qatar: small state, big politics, Cornell University Press, Ithaca, 2015; chapters in Kamrava and Babar in Migrant labor in the Persian Gulf, Hurst & Company, London, 2015).