This book examines the modes by which the grand theories of International Relations can be restructured at the level of meta-theory. It emphasizes the inability of grand theories to make sense of international relations in postcolonial societies and argues to engage in such restructuring in the domain of ontology. This is done by making a historical sociological defence toward adopting mid-level theories in IR. It is a critique of the meta-theoretical foundations of Kenneth Waltz's grand theory of neorealism, by pivoting itself upon the framework of postcolonial ontology. Dwelling upon Mohammed Ayoob's mid-level theory of subaltern realism, it argues for undertaking the task of restructuring International Relations at the level of meta-theory, largely in the sphere of ontology. It explains how the thrust of grand theories such as neorealism, on ontological singularity can be circumvented. Owing to this, International Relations can experience a meta-theoretical transformation that may manifest in the broader engagement of the discipline itself, with the very conception of ontological multiplicity.