This exploratory study investigates teachers' use of metadiscourse in EAP lessons and academic lectures. The analysis is based on two corpora of instructor contributions to classroom discourse: 18 EAP lessons from the L2CD corpus and 18 university lectures from the MICASE corpus. Based on Hyland's (2005) interpersonal model of metadiscourse, the two corpora were compared to examine the influence of pedagogical content and context on teachers' enactment of metadiscourse in the classroom. Findings of the comparative analysis suggest that these aspects of teaching and learning influence teachers' use of metadiscourse in significant ways. EAP teachers seem to be more concerned with explicitly framing the discourse primarily to set up classroom tasks and engendering greater student involvement and participation. On the other hand, university instructors' priority lies in establishing relationships between ideas in the unfolding arguments of lectures. Yet for some metadiscoursal features, the real-time spoken environment of the classroom appears to override pedagogical focus and approach. The paper concludes with a few pedagogical implications.