Book excerpt: The traditional concept of the nation-state as the key player in global affairs is being challenged by the forces of globalization, technological progress, and new forms of governance. These shifts are introducing complexities and uncertainties into international relations, which are leaving scholars, policymakers, and students struggling to keep up with the evolving landscape. The concepts of 'postinternationalism' and 'heterarchy' present promising but largely unexplored frameworks for understanding these dynamics, making a comprehensive resource to navigate this transformation an urgent necessity. Postinternationalism and the Rise of Heterarchy addresses the need to examine postinternationalism and heterarchy as alternative frameworks thoroughly. It compiles chapters that explore theoretical perspectives, empirical case studies, and practical implications across disciplines like political science, international relations, sociology, economics, and law. The book provides a nuanced understanding of the reconfiguration of power and governance in the modern world by investigating the impact of non-state actors, technology, global economic trends, and transnational social movements.