The Blue Card directive is an EU policy instrument aimed at attracting highly skilled workers to the EU. After difficult negotiations, it was agreed upon by 24 EU member states; however, the transposition and implementation of the directive showed divergent levels of commitment towards this tool. In this PhD dissertation, cooperation between EU member states in the field of highly skilled migration policy is viewed as a game of cooperative competition. Under conditions of strong interdependence, states are driven not only by the need for strategic flexibility (competition), but also by the need of cost and risk sharing (cooperation). This dissertation researches (using the theoretical framework of coopetition) the underlying limits of cooperation between EU member states in a policy area where national systems compete to attract a globally scarce number of highly skilled workers. The dissertation, apart from making a diligent analysis of the directive's negotiations, gives a birds-eye-vie of the modes of its transposition and implementation in 24 member states and examines three cases closely: the Netherlands, Germany and Austria.