The Global IR research programme promulgates a borderless ecology of cultures that has only an inside without an outside. This borderless ecology of cultures reinvents the human condition (including the condition of ‘the international’) as perpetually interconnected at the level of consciousness. While Western-centric IR theories depend on (neo-)Kantian philosophies to emphasize the time-space bounded identities of human beings living in visibly divided phenomenal worlds, the de-Kantian philosophies of the Global IR research programme - exemplified by the Tianxia, Advaita, and Nishida Kitaro’s Buddhism-inspired theories - recuperate the temporally-spatially indivisible phenomenal-noumenal flow of human life, thereby facilitating back-and-forth movement between the Westdominated ‘one world’ and the non-West-embodied ‘many worlds’. The central objective of the book is to demonstrate how this back-and-forth movement offers opportunities to conceive of and found a new world order that recognizes the temporally-spatially indivisible human condition on earth. The book delineates a set of guiding principles to promote an innovative practice of theory-building and policy-making that transcends the geo-centric limitations of knowledge-production and knowledge-application, thereby establishing the futuristic foundation of the Global IR research programme.