While there is a growing body of social research on migration and integration of immigrants from third countries arriving into the European Union (EU), this paper draws attention to the intra-EU mobility and integration processes. It is doing so by presenting results of a research on social adaptation practices of highly skilled migrants from other EU countries that temporarily live in Warsaw (i.e. up to five years). The research with people of British, French and German nationality has demonstrated how they create everyday social spaces. Short-term perspective on their own life activities that are driven by their spatial mobility, contributes to development of specific adaptation strategies in which reproduction of the social space constitutes a stable component. Relations with other immigrants and local residents are reproduced and they are selective (created with Poles and other expats of similar traits), spatial (developed in specific places) and temporal (assumed to be short-term). Relations with family and close friends are sustained despite leading a hyper-mobile life. Their transnational social space is flexible regarding its scope and strenght - while social relations in Poland are selective and temporary, social ties sustained with family members and close friends outside Poland are stable and long-term. The research has also exposed a gender dimension in the transnational spaces creation with women who play active role in their reproduction. Everyday practices of women create a sense of "familiarity" and "stability" and constitute a counterbalance for "fluidity" and "changeability" around which mobile lives of their families evolve.