Kwon, Heokseung. 2009. The SNU Korean Learner Corpus of English: Compilation and Application. English Language and Linguistics 28, 203-228. Compilation and investigations of non-native learner English have been a relatively recent enterprise worldwide. It was not until the early 1990s that academics and publishers started collecting corpora of non-native English, which have come to be referred to as the learner corpus. Granger (1998b) is said to be the first systematic collection of learner corpus studies, and studies based on learner corpora have only started to become more widespread in the early 2000s. The availability of various learner corpora opened up a new field of SLA research, but a decent size corpus of Korean learners of English has not been available until recently. The purpose of this paper is to describe a project involving the compilation of a Korean-speaking English learner corpus, to survey existing major learner corpora of English and learner corpus-based studies in Korea, and to illustrate how learner corpus data can be applied to language research and teaching.