In the wake of the Cold War, the Realist mainstream in International Relations is confronted by a crisis of doubt and uncertainty which it has, for so long, sought to contain within a restricted narrative of reality concerning the nature and potentialities of the state system and the modern global subject. This article engages in a critical reassessment of Realist ethics in the search for an alternative 'art of the possible' centred on a reframed notion of the ethical subject and of ethical responsibility. It does so in arguing that post-modernist scholarship has much to offer on the ethics question in International Relations and on the universalist tradition from which the academic discipline of International Relations is derived.