Ukraine's NATO ambitions form a controversial but vital international issue because they implicate the contradictory perspectives of Poland and Russia. The history and self-perceptions of all three states shape and reshape the question of Ukraine joining NATO, as a key step toward westernization, integration, and independence. The challenges of accommodating these competing visions of the past and future are relevant beyond the alliance to all practitioners and scholars of international affairs; in this connection, the question of Ukraine's NATO status also can serve as a case study of the broader subject. The present analysis takes the basic form of a historical narrative that analyzes Ukrainian, Polish, and Russian views of their shared history and divergent visions of the strategic future. This thesis provides a current prognosis as to the likelihood of Ukraine joining NATO and shows the limits and potential of the westernization process, security threats in the region, Russian democratization, and Russian engagement in international relations with NATO and Ukraine.