Previous conversation analytic research has documented various aspects of preference organization and the ways dispreference is displayed in relation to pedagogical focus in L2 and CLIL classrooms (Seedhouse, 1997: Hellermann, 2009: Kaanta, 2010). This study explores preference organization in an under-researched context, an English as a Medium of Instruction (EMI) setting, and it specifically focuses on how a teacher displays dispreference for preceding learner turns. The data consist of 30h of video recordings from two EMI classes, which were recorded for an academic term at a university in Turkey. Using Conversation Analysis, we demonstrate that the teacher employs a variety of interactional resources such as changing body position, gaze movements, hedging, and delaying devices to show dispreference for preceding student answers. Based on our empirical analysis, the ways the teacher prioritizes content and task over form/language are illustrated. The analyses also reveal that negotiation of meaning at content level and production of complex L2 structures can simultaneously be enabled through teachers' specific turn designs in EMI classroom interaction. This demonstrates that preference organization, particularly in a teacher's responsive turns, can act as a catalyst for complex L2 production and enhance student participation. This study has implications for conversation analytic research on instructed learning settings, and in particular on teachers' turn design in classroom interaction. (C) 2019 The Author. Published by Elsevier Inc.