The concept of protection of distressed citizens abroad was born inside the mainstream of theories on ‘Law of Nations’ in the seventeen and eighteen centuries For a long time this concept has been based on the strict relation between State and ‘its’ subjects Since 1992 the new legal order of European Union EU law has given zest to the novel concept of protection of European citizens abroad so that any EU country can intervene to protect unrepresented Europeans in third countries Rule of law and Member State accountability are two basic milestones in EU law and well-settled case law of the EU Court of Justice so that the traditional theories on State immunity and on discretionary power of consular and diplomatic agents cannot reasonably be maintained The present study will conduct an in-depth analysis on Article 23 of the Treaty on the Functioning of the European Union TFEU where the basic provision on protection of Europeans abroad is enshrined