In June 2004, the Association of the Councils of State and Supreme Administrative Jurisdictions of the European Union organised a two day colloquim in the Hague, during which the quality of European legislation was discussed by representatives of the 25 Member States of the EU as well as of the Court of Justice EC. This book is based on the General Report for that colloquium, the various national reports, two reports prepared by members of the Court of Justice EC and the Court of First Instance and the discussions. More specifically the book deals with, i.a., the European and national legislative process, the preliminary rulings procedure as a tool and as a source for the application of European law and the connecting links between the EU and the national legal systems and between the application and the drafting of European and implementing legislation.