Context: During clerkships, teaching and learning in day-to-day activities occur in many moments of interaction among doctors, patients, peers and other co-workers. How people talk with one another influences their identity, their position and what they are allowed to do. This paper focuses on the opportunities and challenges of such moments of interaction between doctors and students during a clerkship characterised by short supervisory relationships. Methods: This study was conducted in a 10-week internal medicine clerkship. Nine students and 10 doctors who worked with these nine students participated by regularly describing moments of interaction, using dictaphones. We performed critical discourse analysis of material sourced from a total of 184 audio diary entries and seven student debriefing interviews to reveal how participants discursively shaped the way they could think, speak and conduct themselves. Results: The ways in which doctors and students posed and answered questions represented a recurrent and influential feature in the diaries. This Question and Answer dynamic revealed six discourses of Basic Learning Need, Care and Attention, Power Game, Exchange of Currency, Distance, and Equality and Reciprocity. These discourses and the interplay among them revealed both students' and doctors' frameworks of needs and expectations in a culturally defined power structure. The interplay among the discourses reflected the ways in which doctor-student interactions afforded meaningful contributions to their medical or educational practice such as in the exchange of authentic professional or personal experience. Conclusions: By purposefully bringing power structures to the surface, we have addressed the complexity of learning and teaching as it occurs in day-to-day moments of interaction in a clerkship with little continuity in supervision. Both doctors and students should be supported to reflect critically on how they contribute to supervisory relationships with reference to, for example, the ways in which they ask or answer questions. © 2014 John Wiley & Sons Ltd.