In this dissertation, I aim to provide a theory on the distribution of structural Case in Korean. I propose the following Structural Case Assignment Hypothesis (SCAH) regarding the assignment of structural Case: "Structural Case is assigned by phase heads (C: nominative; v: accusative) to every argument in the c-command domain of the phase head at the completion of each strong phase." Based on this hypothesis, I provide an analysis on the distribution of structural Case in the following three constructions in Korean: passive constructions, Double Nominative Constructions and the ECM construction. There are several notable properties in the above constructions. First, in the passive construction of the DOC, the theme argument is marked with nominative case, while it is marked with accusative case in English counterpart. Also in the Possessor Raising Construction (PRC), the second accusative DP can be marked with either nominative or accusative case in the passive construction of the PRC. I propose that this nominative-accusative alternation results from the different order in the application of Possessor Raising and A-movement. Secondly, with respect to the DNC, I show that there are two kinds of DNCs. In one type, the predicates are one-place intransitive predicates. In the other type, the predicates are two-place psychological state verbs. Regarding the second type of DNC, I propose that the projection of the light verb which assigns accusative Case is dependent on the existence of an external argument. Lastly in the ECM construction, I show that the ECM construction has a finite embedded CP and places some semantic restriction on the embedded predicate. For the ECM construction, I propose that the embedded subject moves to [Spec, CP] and is assigned a [+Prominence] feature. Then, the embedded subject is assigned accusative Case at [Spec, CP] by the matrix v. Also by being assigned a [+Prominence] feature, the embedded subject requires the predicate to denote an inherent or permanent property of it. To conclude, in this dissertation I consider the exceptional distribution of structural Case in various constructions in Korean and show that SCAH can successfully explain it. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]