Three essays on Immigration and Outsourcing Arsen V. Melkumian This dissertation includes essays on legal and illegal immigrations and outsourcing. Chapter 1 introduces the paths that economics has blazed into in the areas of legal and illegal immigration and outsourcing. The first essay, in Chapter 2, presents a Cournot duopoly model of a domestic unionized firm and a foreign firm, where the domestic firm has an option to shift all of its production abroad. An increase in the bargaining power of an employment oriented union will increase domestic output and utility of the union. The second essay, in Chapter 3, examines illegal immigration in the U.S. from Mexico using annual data on the U.S. border apprehensions of illegal migrants from Mexico and border enforcement. The results support the hypothesis, that recent legal immigrants from Mexico facilitate the flow of illegal migrants from Mexico. This result suggests that large scale amnesties that provide legal status for illegal immigrants should be avoided, as they provide unhealthy stimulus for future illegal immigration. The third essay, in Chapter 4, develops a gravity model of legal immigration using balanced panel data. Higher index of Economic Freedom is found to be associated with increased migration flows. Chapter 5 provides the summary of the dissertation and concluding remarks. Now that I have come to completing my degree, I realize it would have been impossible to accomplish it on my own. Many people have helped me along the way. I wish to express my sincere appreciation and gratitude to my dissertation advisor Santiago Pinto without whom this body of work would have been impossible. Thank you for your continuous support and exceptional guidance. I truly appreciate all of your help. I am deeply grateful to the members of my dissertation committee: Ronald Balvers, Stratford Douglas, Alexei Egorov and Andrei Smirnov, for all their constructive comments and input in this work. To Nicki Metts, thank you for always being there when I needed your help. To Saurav Roychoudry and Serhiy Kotsan, thank you for sharing valuable thoughts and information with me and for helping me at any time. Finally, I would like to express my sincere thanks and appreciation to my wife, Alla Melkumian, for her support and encouragement.