This article analyses the main debates over the application of the Charter to disputes between private parties and assesses the ways in which the case law over the last ten years has responded to them. The article goes on to propose an alternative schema, whereby horizontality can be understood as a structural principle of EU fundamental rights adjudication on its own terms, rather than as an extension of the direct effect doctrine. It is argued that a self-standing principle of horizontality with equally valuable—yet operationally distinct—direct, indirect, and state-mediated manifestations, could respond more coherently to the conceptual, procedural, and remedial challenges displayed in the case law.

On 15 January 2014, the Court of Justice (hereafter ‘the Court’) delivered its judgment in Association de Médiation Sociale (hereafter ‘AMS’). AMS brought for the first time before the Court the issue of horizontal applicability in relation to a provision of the EU Charter of Fundamental Rights (hereafter ‘Charter’), namely Article 27 thereof, which enshrines the right of workers to information and consultation within the undertaking. The case therefore raised questions of ‘undeniable constitutional significance’, as Advocate-General Cruz Villalón had put it in his Opinion, regarding the post-Lisbon enforcement and interpretation of the Charter and, in particular, its application to disputes between private parties.