Social scientists in the modernization school argue that industrialization and modernization lead societies to be "open" societies characterized by equal opportunities and a central importance of individual efforts and achievements in social mobility. They assume, using nation-states as the unit of analysis, that stratification takes place primarily and exclusively within nations. This study, by contrast, perceives stratification and social mobility as processes taking place globally. Shifting its focus from national dimensions to global and transnational dimensions, this study investigates the global social mobility of South Koreans, including Korean immigrants in the United States.

This study situates income earnings and social mobility of non-migrant South Koreans and Korean immigrants in the United States within broader patterns of transnational and global social mobility, and reassesses the relative weight of categorical attributes (e.g. country) with that of human capitals (e.g. college education). The results suggest that how social stratification, despite the modernization of South Korea and the United States, remains shaped by categorical inequalities. In this sense, achievement and ascription, as criteria of selection, continue to be fundamental to global stratification. The role of achievement is far more modest than usually assumed when compared to the continuing impact of categorical attributes such as race/ethnicity and nationality.