The dramatic shift of the Indian subcontinent, once highly integrated for a millennium until its Partition in 1947, into one of the world's least integrated regions, raises questions about this swift transformation. The formation of the South Asian Association for Regional Cooperation (SAARC) by the newly partitioned states aimed at fostering collaboration. However, initial efforts proved futile, prompting a comparison with the successful dynamics of the European Union (EU) and the Association of Southeast Asian Nations (ASEAN). Drawing on his experience in the Bangladesh foreign ministry and as a World Bank consultant, Ambassador Tariq Karim's book provides insights into South Asian regional cooperation. It traverses history, analyses cooperation models, examines various dimensions of collaboration, and envisions extending sub-regional cooperation to the broader Bay of Bengal region. Ambassador Karim's narrative highlights contrasts between SAARC's challenges and the achievements of the EU and ASEAN, emphasising key factors that differentiate successful regional initiatives. This book not only serves as a documentation of historical shifts but also envisages a future where the Indian subcontinent and its neighbouring regions embrace enhanced collaboration for mutual benefit.