Socio-economic interdependence and supranational integration are not linear processes in the recent European experience. Similarly, responses in terms of de-bordering and re-bordering, including those influenced by national-populist stances, are not necessarily univocal. Dealing with a relevant strand of literature in psychology and political science, the chapter stresses ambivalent perceptions of cross-border relations. In particular, the analysis focuses the opinions by citizens towards cross-border workers. Using an original survey data, it shows how a relevant part of citizens support the idea that cross-border workers reduce prosperity and exacerbate unfair competition at the expense of residents, and, at the same time, make an important contribution to regional economy. The ambivalence reflects the awareness, also among national-populist supporters, that without cross-border workers, it is impossible to the defend the regional prosperity of a strongly integrated border region.