This reference for a preliminary ruling concerns the question whether an administrative act which has been ratified by the legislature can be excluded from obligations under the Environmental Impact Assessment (EIA) Directive 85/337/EEC and the Aarhus Convention. The reference has been made by the Cour constitutionelle of Belgium in proceeding brought by persons residing near airports and a railway against the Region of Wallonia for ratifying building consents at those installations. The residents argue that the obligations under the EIA Directive as well as the Aarhus Convention have been “bypassed” as the Conseil dÉtat ‘ratified an administrative act, making those projects fall outside the scope of the two instruments The Court made the initial observations concerning the conditions for the exclusion of a project from the scope of the EIA Directive. As of Art. 1 (5), a legislative act adopting a project must be specific and display the same characteristics as a consent of that kind. The project must also be adopted in detail and include all the elements of the project relevant to the environmental impact assessment. Moreover, the legislative acts are only excluded from the scope of that directive when the legislative body has substantively fulfilled the objectives of the Directive, particularly that of supplying information. Accordingly, the Court is of the opinion that only projects the details of which have been adopted by a specific legislative act, in such a fashion as to achieve the objectives of the directive and Convention by the legislative process, are excluded from the scope of those instruments. Thus, the national court has to verify that those conditions have been satisfied, taking into account both the content as well as the procedure of the act adopted. In its ruling the Court followed its previous rationale from the Boxus and Others Case C-128/09, that a legislative act which only ratifies a pre-existing administrative act without a substantive legislative process, cannot be regarded as an act sufficient to exclude a project from the scope of the EIA Directive. This strengthens the safeguards put in place by the EIA Directive and the Aarhus Convention that which projects likely to have significant effects on the environment are made subject to an environmental impact assessment before consent is given. Interestingly, the Court concluded that the Implementation Guide to the Aarhus Convention is to be treated as an explanatory document … capable of being taken into consideration … for the purpose of interpreting the Convention.