This article contextualizes second language use in an Australian university’s departmental interactions, among students and staff, to explore international students’ negotiations of identity, legitimacy and professionalism. Profiling four doctoral students with diverse language and cultural backgrounds, the study observes out-of-classroom departmental interactions as avenues for the negotiation of ‘institutional identity’. The findings highlight the diversity of the strategies applied by these students for communication and integration despite their common challenges as newcomers to a Western university. The discussions underline the role of agency and intentionality in participation and learning through interaction and challenge the all-purpose ‘international student’ label.