This thesis attempts to explain the change in Turkey’s foreign policy regarding Cyprus between 2002 and 2004. It argues that the overriding factor in this policy change was a change in leadership, i.e., the coming to power of the Justice and Development Party (AKP), which developed a decidedly liberal outlook on foreign affairs following its split in 2001 from the anti-Western, Islamist Welfare Party. Other crucial determinants included the Europeanization of the Cyprus issue and selective support for interest groups within Turkey, both of which were affected to various degrees by the European Union and a propitious change in decision-making context. This thesis shows how constant policy failures during the 1980s and 1990s led to an identity crisis and the subsequent radical ideational transformation of the AKP whereby the party leadership renounced political Islamism and began to espouse an EU-oriented policy agenda and compatible rhetoric. The arguments presented in this thesis contribute to the literature on foreign policy analysis, political leadership and Europeanization. With regard to foreign policy analysis, this thesis shows that foreign policy change is a multi-causal phenomenon that can only be explained by a combination of various concepts. Moreover, it argues that despite the fact that no ready-made formula can account for all cases of foreign policy alterations, changes in leadership and a favourable decision-making composition appear to be indispensable determinants of any foreign policy shift. With regard to leadership, by applying a social-learning model to the analysis of the AKP leadership, this thesis follows the evolution of the Turkish Islamist Movement towards conservative democracy and an embracing of EU norms, which in turn resulted in a change in Turkey’s Cyprus policy. It is argued that Turkey’s new Cyprus policy was above all the consequence of a radical normative shift in the mindset of the new Turkish leadership. With regard to Europeanization, this thesis demonstrates how the change in Turkey’s foreign policy vis-à-vis Cyprus was bolstered by the Europeanization process. In this context, it can be understood that the EU militated in favour of a policy alteration by Europeanizing the Cyprus disagreement with the acceptance of the Republic of Cyprus into the EU in May 2004. The third essential determinant of Turkish foreign policy shift was the emergence of a propitious decision-making context within Turkey, which rendered such a policy shift possible.