Buzan and Lawson’s The Global Transformation establishes that many of the basic parameters of world politics originated in the ‘long 19th century’. Despite finding much to admire in their book, we are concerned that it lacks an explicit theory of change. In its drive to highlight the novelty and exceptionalism of the 19th century, it offers insufficient guidance on two key issues: first, how international relations scholars should situate Buzan and Lawson’s ‘global transformation’ in existing debates over transhistorical processes; and, second, how they should apply lessons from that transformation to understanding emergent trends in the contemporary world. We argue that a more explicit study of causal factors might help account for why the 19th century was unusual. We conclude with thoughts about how the field should proceed after The Global Transformation. In particular, it points to how concatenating changes could profoundly alter international politics – an approach we term ‘Exotic International Relations’. Buzan and Lawson’s book therefore serves as a marker for the importance of systematically theorizing how radical potentialities for transformation might rearrange existing structural assemblages in world politics.