This chapter provides a comprehensive analysis of the political dynamics within Serbia, focusing on polity, policy, and politics in relation to horizontal cooperation. It argues that while Serbia has significant untapped potential for horizontal collaboration, this potential remains largely unrealised due to the centralised dominance and hegemony of the ruling Serbian Progressive Party. The chapter also highlights the supportive role of the European Union (EU) and European countries in facilitating these cooperative efforts through financial backing and logistical assistance. It underscores the crucial importance of sustained support from these entities in fostering democratic restoration and, consequently, creating an enabling environment for autonomous cooperation and coordination among local authorities. However, the chapter also explores the complexities of Serbia’s relationship with the EU, particularly due to ongoing negotiations between Belgrade and Pristina, as well as Serbia’s close ties with Russia and China. These factors pose challenges to the smooth progression of Serbia–EU relations and may hinder efforts to promote horizontal cooperation within Serbia’s political landscape.