Lee, Shinsook and Cho, Mi-hui. 2000. Cooccurrence Restrictions and Optimal Syllabification in English. Journal of the Linguistic Association of Korea, 8(3), 123-138. In this paper, we examine the cooccurrence restrictions in American English: coronals are prohibited from occurring before [y] in syllable-initial position; the sequence of a coronal and [y] occurs only in unstressed medial position, and the vowel which follows the sequence must be [u] but not others. First of all, we show that the cooccurrence restrictions can be accounted for within Correspondence Theory, without a strict rule ordering. In particular, we show that optimal syllabification, which is determined by a constraint hierarchy where markedness constraints dominate relevant faithfulness constraints, provides a unified account of the cooccurrence facts without several derivational steps. We also demonstrate that the occurrence of the sequence of a consonant plus [y] only before the vowel [u] can be accounted for by positing the input representation of the vowel [u] as /ru/, thus dispensing with an abstract underlying representation or ad-hoc rules for [yu]. Moreover, we do not need to employ controversial resyllabification in order to account for the distributional facts concerning the sequence of coronal-yu in unstressed medial position. (Hoseo University and Pukyong National University)