Although neither legal order deliberately set out to deal with complex matters of labour law, the European Union (EU or Union) and the European Convention on Human Rights (ECHR or Convention) have both had a large impact, in one way or another, on labour law matters. By creating an (admittedly complex) external supervisory system to review the legality of EU action, while also internalising the values the Convention within the EU legal order, the Union's formal accession to the ECHR is an(other) important constitutional moment for the EU in several respects, all of which deserve careful consideration. In the field of labour law in particular, an embedded inclusion of human rights-type guarantees into the EU legal order has long been advocated by many commentators to counterbalance a perceived prioritisation of market freedoms. This chapter seeks to understand how accession will affect the EU legal order, building on three constitutionalâ models through which we can understand EU law and the ECHR. In what way will accession affect our constitutional understanding of the Union, and how will this affect labour law? Much constitutional theorising regarding the EU has focused on two broad models of constitution: a hierarchy-based model which stems from the autonomous nature of EU law and the constitutional role of the EU Treaties, and a value-based model which considers the interaction of competing legal sources and their principled resolution. It will be argued that while the ECHR will not affect the hierarchical supremacy of EU law by virtue of the ECHR's particular legal structure, its new supervisory role and embedded constitutional values will inevitably impact upon labour law in the EU. However, this chapter argues that a third, much neglected, model of constitution must be grasped to understand the place of labour law in the EU. Labour law is here presented as part of an industrial constitution, stressing the law's constitutive function with regard to social actors and the market. It will be demonstrated that the impact of rights-based judicial supervision of the Union will be inherently limited on the industrial constitution, as this supervisory structure embodies a purely liberal vision of constitutional review which can police actors and norms, but cannot directly reconstitute market actors according to constitutional values such as democracy, dignity or solidarity. As significant as the constitutional moment of accession might be, transformative reform of EU labour law is unlikely to come, in the first instance, from accession to the ECHR, and is ultimately dependent on a legislative restructuring of the internal market of the EU, and in particular an incorporation of values of citizenship into the market. Accession my cast light upon the need for such reforms, but is intrinsically limited in its ability to achieve these changes.