This article explores four aspects of the underdeveloped conceptualization of the role of international migration in uneven regional development and polarization in cities. First, it emphasizes the way in which human mobility transfers not only human capital but also knowledge and material capital, and that these are interrelated. Second, it considers how changes in the nature of mobility have implications for uneven regional development. Third, it develops the concept of enfolded mobilities, as a way of understanding how individual migrations are directly enfolded with those of other individuals, either through associated or contingent movements, or through consequential migration at later stages in the life course. Finally, it discusses how governance impinges on and mediates the key relationships between mobility and uneven regional development.