In the institutional design of the EU, the CJEU acts as the judicial branch. The role of the CJEU is to provide the judicial safeguards necessary to ensure that the law is observed in the interpretation and application of the treaties and generally in all of the activities of the Union. As mentioned above, the European integration is governed by the rule of law. Its very existence is based on the recognition by the Member States, by the EU institutions and by individuals of the binding nature of its rules. Therefore, the CJEU safeguards the legal foundations of the European integration, provides it legitimacy and also fills in the gaps in the written rules.