This study examines the nature of small-group discussion and explores how it fosters oral academic discourse socialization in a TESOL postgraduate course. The participants included four native-English speaking and six non-native English Speaking postgraduate students at a state university in the U.S. The findings revealed that small-group discussions provided a context in which students were gradually socialized into the discipline-specific discourse and the practices of an ESL/EFL professional. The feature of discourse socialization in small-group discussion was expressed through the participants' identity-construction, critical thinking, and making intertextual connections. Both NES and NNES participants, experienced and inexperienced alike, were able to draw on their unique perspectives and expertise to solve the problems presented in discussion prompts. Pedagogical implications on incorporating small-group discussions to facilitate oral academic discourse socialization are also discussed. (Contains 1 table.)