The chapter examines the principles of regional formation through the lens of comparative regionalismRegionalism, focusing on BRICSBRICS as a case study. It explores the evolution of regionalism from its “old” form, which emphasized geographic proximity and economic-military alliances, to “new” and “comparative” regionalism, which accounts for socio-cultural diversity, multipolarityMultipolarity, and globalized systems of international relationsInternational relations. Employing methods such as comparative, historical, and conceptual analyses, the study highlights how BRICS exemplifies transregionalismTransregionalism, functioning as a flexible and multidimensional platform for cooperationCooperation beyond territorial boundaries. Key principles identified include the absence of rigid institutional structures, consensus-based decision-making, and integrationIntegration across economic, political, and socio-cultural spheres. The analysisAnalysis underscores BRICS's unique role in fostering global cooperationGlobal cooperation among countries with varying economic and political systemsPolitical system, emphasizing its commitment to addressing global challenges such as economic inequality and geopolitical imbalances. Despite its successes, the study notes significant challenges, including the lack of institutional cohesion and divergent priorities among member statesState. The chapter argues that BRICS’s innovative approach to regionalismRegionalism not only provides alternatives to Eurocentric models but also contributes to a more equitable global order by emphasizing collective action and mutual respect. By addressing these principles and challenges, the study presents BRICS as a transformative actor in international relationsInternational relations, capable of redefining regional cooperation and advancing the global discourse on multipolarityMultipolarity. This comprehensive exploration of BRICS’s role in comparative regionalismRegionalism contributes valuable insights into the dynamics of modern regional integrationIntegration and its potential to influence the future of global governance.