In this paper some issued related to interpreter-mediated communication for public services are examined. It is argued that the encounter between host country and migrant is governed by power relations where hierarchy is constructed along a number of different axes: cultural, historical, institutional, political as well as communicative. The paper identifies some of the overt and covert power differentials which could become potential stumbling blocks in public service interpreting, both linguistic and language related features, such as: metaphor and truth value, connotation, mismatching of semantic fields, paraphrasing explicit language, social role and identity embedded in grammatical markers, indirectness as a politeness marker, turn-taking and direction.