The author advocates a flexible approach with respect to the interpretation of the term “Member State” as employed in the Succession Regulation, allowing the differentiation between “participating” and “non-participating” States. It does not mean that the term “Member State” should always be interpreted in a wide sense including the three non-participating States: Denmark, the Republic of Ireland, and the United Kingdom. Whether a wide or a narrow interpretation is appropriate depends on the context and the purpose of the single provision. Most provisions contained in the chapter on jurisdiction refer to participating Member States only. But some articles such as the Article 13 of the Regulation, provide a counter-example. A uniform interpretation of the concept of Member State in all provisions of the Succession Regulation seems far too sweeping. It reminds of Begriffsjurisprudenz and does not take account of the purpose of the single provisions. In particular, it disregards the need for the cross-border protection of individual rights in a Union with open frontiers.