This thesis has two broad goals. The first is to contribute to the study of Arabic phonology particularly syllable structure and syllabification. This will be achieved through examining phenomena related to syllable structure and syllabic weight such as syllabification, stress assignment, epenthesis, syncope, and sonority in three different varieties of Arabic: Classical Arabic, Meccan Arabic, and Hadhrami Arabic. There will be a focus on the analysis of superheavy syllables from an optimality-theoretical perspective. An original contribution in this regard is the introduction of new data from Hadhrami Arabic, a dialect spoken in Ghayl Bawazir, Hadhramawt, Southern Yemen, that has not been the subject of previous phonological analyses. The second goal of this thesis is to touch upon controversial matters in phonological theory such as the analysis of morphologically conditioned phonology and phonological opacity. It will be shown that some of the data presented in this study are best analyzed with reference to the morphological properties of the input and allowing for candidate evaluation at different levels of the morphology, thus presenting a challenge to the output-oriented and parallel nature of classical Optimality Theory. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]