The world has witnessed the proliferation of Mega-Regional Trade Agreements (MRTAs), and this book critically examines a range of issues with MRTAs starting from their genesis to their economic clout over the world, the likely implications for member countries' integration, and the challenges they pose for non-member countries.Gaur focuses on concerns and challenges that non-member countries like India, South Africa, and Argentina, among others are facing with the World Trade Organization (WTO) standstill and how these MRTAs are becoming a cause of concern for the multilateral trade organization. The book also discusses the major reasons for India's withdrawal from Regional Comprehensive Economic Partnership (RCEP) and tries to answer these questions - Should India join RCEP or the Comprehensive and Progressive Agreement for trans-Pacific Partnership (CPTPP)? Taking into account India's economic and strategic concerns, various models and indices are used to evaluate the effect on trade and investment. It also emphasizes the trade and investment linkages of India in these mega-regionals and the consequences for MRTA member countries. The consequences of India's absence from the RCEP and mega-regionalism in general are also examined.This book is useful for research scholars working in the field of international economics as well as government aids and policymakers. It will also be valuable for classes in international trade and integration, international relations, international security and regional studies.