As time goes by... it was in summer 2014 when the publisher discussed with us the idea of an international commentary on European labour law. This follows a tradition in continental systems, especially in Germany, where commentators all over the country analyse statutes, even those of minor importance. Therefore, the German publishing house Nomos took the initiative to commence this project, given that there are still rela- tively few commentaries on these important norms at international level. We discussed the concept and we were quickly convinced that a commentary from a European perspective could provide additional value for any legal practitioner, as well as for legal scholars. The commentary should provide information in order to grant a spe- cific European view, taking into account current legal debates with an EU law context. After a short period of discussion, we concluded that this book should not only provide observations on the EU legal framework. Instead, we wanted to include also internation- al and regional labour law: specifically, the International Labour Organisation and the Council of Europe. This reflects our conviction that it is not sufficient to consider only EU legal instruments, notwithstanding their important status in many of our jurisdic- tions. By adopting a wider perspective, we can find both old and new tools that enrich our interpretation of domestic labour law. Moreover, looking beyond the EU provides us with external benchmarks against which to evaluate the sufficiency of current EU labour law.