Based on ethnographic data collected on the establishment of call centres in France and the Maghreb by a French insurance group, the article addresses the notion of 'voice', as an object and an analytical tool, to reveal the mechanisms for legitimizing the call centre workers' voice. It shows that the pursuit of an objective of economic profitability of the interaction through the professionalization, standardization, and delocalization of the employees' voice does not produce the expected effects. Phenomena of discrimination and domination act through and on these voices, inseparable from the social spaces in which they are produced and heard.