This study focuses on three main questions: What does citizenship mean for immigrants? Why do some immigrants decide to acquire host countries' citizenship while others do not? Do citizenship and migration policies of countries (such as Canada and Germany) are related to the decision-making process of immigrants? More specifically, the objective of the study is to investigate high-skilled and business Turkish immigrants (HSBTI) who moved to Germany and Canada between 2000 and 2010. It is expected that immigrants' naturalization decisions and conceptualization of citizenship are related to countries' migration and citizenship policy approaches (such as restricted or multiculturalist). With respect to high-skilled and business Turkish immigrants, this study put forwards the view that host country citizenship and migration policy (whether it is restricted or multicultural); economic, social and political benefits and costs of host country's citizenship; and individuals' conceptualization of citizenship (as a sense of belonging or commodity) influence their naturalization decisions. ContentsINTRODUCTIONCHAPTER ONE. A Conceptual Framework on Citizenship and NaturalizationCHAPTER TWO. Migration and Citizenship Acquisition in Canada, Germany, and TurkeyCHAPTER THREE. Conceptualization of Citizenship: A Comparative AnalysisCHAPTER FOUR. Reasons For Citizenship Acquisition: A Comparative AnalysisCHAPTER FIVE. ConclusionsAppendix 1: Interview QuestionsAppendix 2. List of the Case SummariesAppendix 3. List of the Legal Documents