This paper examines how L2 learners of Korean manifest pragmatic competence in their use of address terms in computer mediated communication (CMC) and how they use these terms to negotiate their identities. Four UK-based learners of Korean with competence levels ranging from Novice High through Intermediate High participated in the study, contributing transcripts of CMC interactions and participating in retrospective interviews over a three-month period. Qualitative analysis of the data shows that CMC provided a fertile context for these learners to manifest pragmatic competence in the use of address terms and to progress beyond classroom learning. Address terms also worked as powerful tools for these learners to establish intimate relationships with Korean acquaintances and negotiate identities as legitimate speakers of the language. However, this process of identity negotiation was complicated by gaps in their pragmatic competence, their preexisting identities and differing expectations on the part of Korean interlocutors. Ultimately, the analysis shows that the question of what constitutes "appropriate" use of address terms in CMC interactions involving L2 learners of Korean is unstable and open to negotiation. The implications of this finding for future research and for KSL (Korean as a Second Language) teaching methodologies are addressed in the conclusion.