In the 1990s, Istanbul regained its long-forgotten role as a regional gateway between Asia and Europe. With the growing importance of the city in global flows, hypotheses concerning the global city and social/spatial polarisation were advanced for Istanbul, arguing that it could best be characterised as a 'divided city'. This paper suggests that despite the city's growing integration with global dynamics, the degree of segregation is not on the rise but even registered a slight fall between 1990 and 2000. The distinct nature of social mobility that provided the poor with the opportunities for upward mobility generated an easily legible pattern of segregation. In the mid-1990s these dynamics changed and the forces acting upon segregation became too diversified to be reduced to a single factor, generating unpredictable results in parts of the city. Our findings indicate that the mobility of the existing population and locational choices of newcomers work in opposite directions as far as their impacts on segregation are concerned, with the former increasing and the latter decreasing the existing levels of segregation.