Article 53 of the vienna convention on the law of treaties provides that a treaty is void if it conflicts with jus cogens. It is theoretically possible that two or more states would conclude such a treaty, yet this is not very likely in practice. The question thus arises how jus cogens operates outside of article 53 situations and outside of treaty law in general. A ‘trumping effect’ of jus cogens over all other norms of international law has been proposed in some writings and judicial decisions. Such views have been shattered by the icj, most recently (but not exclusively) in germany v. Italy. Jus cogens seems to be back to article 53 and its (rather theoretical) voiding powers. Considering the latest judicial decisions, this article aims to place jus cogens within the international legal system. It demonstrates that jus cogens is not a futile concept; but it is wrong to see it as a trump card.