Chapter 1 introduces new Asian regionalism as a paradigm shift in international economic law. It discusses three waves of global regionalism with a focus on the Third Regionalism and its unique characteristics. To promote interdisciplinary dialogues, the chapter explores theoretical debates on regionalism and the normative framework of the New Regional Economic Order, which explains the changing North-South relations in the multilateral trading system. In the post-war era, Asian regionalism has been based on the ASEAN-centered regime known as the ASEAN Plus Six framework. Finally, the chapter provides an overview of the structure and objectives of the book.