The European continent has only one micro-state that is not landlocked: the Principality of Monaco. This city-state along the French Riviera is an independent state under international law and is not an EU Member State. Therefore, the law and policy of the EU’s external relations applies, which must cater for the Principality’s peculiar existence because of practical necessity. The EU retains differentiated legal relations with its closest geographical neighbours, and the EU-Monégasque relationship sees several unilateral EU measures taken to account for Monaco, as well as a limited array of international agreements between the parties, including a monetary agreement. These cumulatively make up the legal aspects to their international relations with each other. At first sight, these legal relations appear limited. Yet, as this article establishes, EU-Monégasque legal relations have widened and deepened over time, and an association agreement is on the horizon to account for the necessitated intensity of cooperation on a legal footing. Such a development would bring the Principality legally closer to the EU than it ever has been before.