This ambitious, innovative project examines the principle of effective judicial protection in EU law over two volumes. The principle of effective judicial protection is a cornerstone of the EU's judicial system and is re-affirmed in Article 47 of the Charter of Fundamental Rights of the European Union. Since the 1980s the Court of Justice has used the principle to shape EU and national procedural rules; more recently, the principle has acquired an even more central role in the EU constitutional structure. In this first volume, an expert team explores how the Court of Justice has interpreted the principle, as expressed in particular by Article 47 of the Charter, in selected policy areas, and reflects on the impact of the principle on the EU's constitutional structure. Addressing key questions such as legal certainty, judicial independence and procedural autonomy, this volume significantly adds to our understanding of judicial protection within the multi-level EU judicial architecture.