In this paper, the linguistic manifestation of an authentic case of interpreter-mediated doctor-patient communication (a briefing for informed consent) is analysed from the perspectives of various disciplines. With only the transcript as their common ground, analyses from the vantage points of Functional Pragmatics, Conversation Analysis, Interpreting Studies, and Health Sciences yield different findings, particularly with regard to the performance of the ad hoc interpreter involved. The paper demonstrates that an interdisciplinary approach to authentic discourse data can lead to an enhanced understanding of the multiple dimensions and functions of language and language use in mediated doctor-patient communication.