This presentation seeks to analyze the historic decision rendered by the Portuguese Constitutional Court on July 15, 2020, regarding the relationship between European Union (EU) Law and Portugal‘s fundamental law as well as discuss its impact. In the judgment, the Court recognized its incompetence to assess the validity of an EU legal norm considering the principles enshrined in the Portuguese Constitution. This position is based upon its reading of Article 8 section 4 of the Constitution which points towards the application of the principles of direct effect and the primacy of the EU law in the legal order of the Member States. In sum, the Court reaffirmed, with some minor reservations, the principle of the primacy of Union law over the law of the Member States, including the Constitution, as well as the exclusive competence of the CJEU to assess the validity of EU law. Furthermore, it linked this exclusive competence to the specificity, autonomy, and integrity of the EU legal order.