The overall purpose of this study is to analyze the acquisition of English word-stress by Arabic speakers in light of advancements in Optimality Theory. It has been reported that Arab second language learners of English have difficulty in acquiring the various patterns of English word stress. According to OT, the reason for this difficulty is that although these speakers, like native speakers, have full command of the universal and violable constraints that are operative in determining where stress falls in the word, they fail to capture or induce the exact ordering of these constraints. The basic premise of OT is that each grammar is a unique way of ordering the set of universal and violable constraints that determine the actual output form of a certain linguistic feature, say word-stress in this case. In other words, whereas Arabic word-stress and English word-stress are both subject to the same set of universal and violable constraints, they differ in one respect: the ordering of these constraints. The sole task of the learner then is to capture the correct ordering that determines which syllable in each word carries main stress.