As its raison d'être, transnational and global sociology attempts analyses of globalized realities; however, it does not necessarily succeed in creating social theories. How can it create social theories using transnational/global sociological imagination ? This article focuses on the relationship between international migrants and citizenship in terms of policy and explores the prospects of theorization from three viewpoints. First, a research topic should be worth being theorized about and should have the potential to develop into one of the several forms of explanatory theories. Second, theorization regarding relationships between international migrants and citizenship substantiates the need to fully develop a national framework, such as the Hammar = Koido = Tarumoto model (the HKT model), in order to understand globalized realities. Finally, to transcend the limits of a national framework, the research incorporates international environment, where international regimes and international human rights norms exist, as a factor into a social theory. This investigation provides the following general implication for transnational and global sociology: The analysis of globalized realities should not underestimate national frameworks and should not deify transnational frameworks.