This article reports empirical findings from an ongoing investigation into the acquisition of second-language (L2) phonemic contrasts. Specifically, we consider the status and role of the phenomenon of hypercorrection in the various stages through which L2 learners develop and internalize a target language (TL) contrast. We adopt the prevailing view in both sociolinguistics and second language acquisition studies that hypercorrection results from a certain amount of linguistic insecurity on the part of the speaker. Based on 53 Korean speakers' production of English target phonemes, we conclude that a series of hypercorrection errors may well represent the final stage in the acquisition of a contrast, and further, that in order for hypercorrection to occur, there must be a formal connection between the TL contrast being acquired and the phonological structure of the learner's native language. (Contains 3 tables, 6 figures and 4 notes.)