This study investigated how adult second language learners negotiate their social, relational identities in real-life communicative interactions within professional, institutional social settings. Based on the sociocultural approach to identity formation (e.g., Lantolf & Pavlenko, 2001; Penuel & Wertsch, 1995), this study examined five Korean graduate students’ experiences with and perspectives regarding their real-life communicative interactions within U.S. academe. The study findings suggested the importance of English learners’ enactment of positive, relational identities in enhancing their agency in order to actively participate in English communicative practices and continue to improve their English proficiency. Pedagogical implications for enhancing Korean students’ agency in learning English were also discussed.