In EU migration studies, sending and transit states' compliance with destination states' migration control policies is often explained as the result of the EU and the member states successfully wielding pressure and persuasive bargaining power. This thesis argues that sending and transit states do not cooperate because they are persuaded to do so by the superior power and are subject to pressure exercised by the EU member state, but because of a long bargaining process between the two countries in which bilateral, multilateral, geopolitical factors and bargaining strategies all play an important role. Migration control cooperation cannot be understood by just analyzing the relations between the EU and its neighbourhood countries, but instead needs to be analyzed in the terms of bilateral relations and the influence of linkages, interdependence relations and embedded processes between EU members and neighbour states. Moreover, by examining the terms and factors of migration control cooperation between such pairs of states, I demonstrate how the latter can enhance their bargaining position by cooperating strategically and conditionally. Through an in-depth analysis of over twenty-five years of the Spanish-Moroccan migration control cooperation I explain the reasons of Moroccan (non-) cooperation over certain periods of times, geographical areas and measures, as well as the structure of the terms of their collaboration. The findings prove that Morocco has instrumentalized migration in order to obtain bargaining power. In other words, through migration control cooperation Morocco has gained power in economic, political, diplomatic, and regional terms. By applying a strategic conditional cooperation on migration control, refusing to implement certain migration control tasks, using the interdependence framework in its favour, taking advantage of the international context and implementing a successful bargaining strategy, Morocco has over the years become a key partner for Spain and the EU with a strong and privileged bargaining position in the North-African, Mediterranean and international arenas.