This edited volume aims to address the gaps in research on the United Nations (UN)'s participation in intergovernmental relationships by delving into the working mechanisms of the United Nations Security Council (UNSC). The book offers a novel overview of the voting procedures of the UNSC and related outcomes in practice; most significantly, it examines members' voting behaviour, veto power, power dynamics, and diplomatic means of sponsoring resolutions and forming coalitions in the Council. It also analyses the role of small, emerging, and regional powers inside the UNSC, alongside their trajectory into the power dynamics of this UN body. It assesses the intertwined relationship between the UN and the European Union (EU). Each chapter demonstrates the challenges and the workings of multilateralism in one of the most significant organisations for global cooperation.