Vulnerability is a concept that stems from ethics and legal theory. It has progressively gained momentum in international human rights law, in particular in the European contextof the European Court of Human Rights adjudications. Also, the European Union is sensitive to it.By the introduction of competences in the Area of Freedom, Security and Justice (AFSJ) we are witnessing a progressive “vulnerabilisation” of EU law. This article intends in the first place to outline such a problematic notion and then to highlight the normative effects of vulnerability. In particular, this article will put forward the argument that such notion could serve to revamp the profile of “justice” of the AFSJ, which has been neglected so far, calling for the development of a more sophisticated ethics of State duties.