What works to make EU law work? This may well be one of the most important questions facing the European Union in view of its alleged implementation deficit. Amongst the variety of tools that the European Commission has at its disposal to compel compliance on the part of the member states, post-legislative guidance is one of them. With tools such as interpretative rules, decisional acts and compliance templates, the European Commission attempts to stimulate member states to comply. We do not know much about how these tools are used by the European Commission or about how these tools are perceived by national implementation actors. This paper analyses the usefulness of post-legislative guidance: to what extent do such tools support domestic actors in the implementation of EU law? The current study presents new empirical evidence on the application of EU directives on product safety, air safety, and pollution prevention. Based on interviews with EU actors and with domestic actors responsible for the application of these directives in the Netherlands, Poland and Portugal, this study illustrates that these actors find this form of guidance very valuable, but that how this works differs across policy domains and countries.
