The social context in which communication takes place heavily impacts upon language. There are not only cultural assumptions in play, but also institutional power and interactive power. Public service interpreters enjoy little institutional power but rather more interactive power. Blommaert’s notion of ‘voice’ can be applied as a key concept for PSI interpreters. In monolingual interaction, for example, asylum seekers get very little uptake of their words, while the asylum seeker always takes up the asylum adjudicator’s words. Meanwhile, the notion of ‘communities of practice’ may be applied for exploring and explaining PSI. Interpreters, and the professionals they assist, for instance, in law courts, sometimes in the medical world, sometimes in immigration settings, may perceive of the public service interpreter as belonging to a common, institutional community of practice, and not to separate ones, due to the poor recognition and weak professional status of the interpreter. With these notions in mind, in this chapter, the author analyses several sets of data in order to explore the social pragmatics of interpreting.