This essay examines the complex relationship between international law and the balance of power which Hedley Bull claims is paradoxical. Bull argues that the balance of power is an ‘essential condition’ of international law and that the actions required to preserve the balance ‘often involve’ violation of international law. It is shown that what seems to be a paradox is not a paradox but essentially a normative problem related to the difficulties in regulating power within international society, and that the perceived paradox does more to obscure than to clarify the fundamental normative problem to be dealt with.