Since 17 August 2015, the Succession Regulation is applicable in the European Member States, establishing uniform rules on the jurisdiction and applicable law for cross-border successions. The Succession Regulation also introduces a European Certificate of Succession, allowing heirs, legatees, administrators of the estate and executors of wills to prove their legal capacity and rights in another Member State. As such, the European Certificate of Succession offers a supranational alternative to national instruments with a similar purpose which exist in many Member States, but often do not produce their full effects abroad. In general, the European Certificate of Succession's legal regime is comprehensive and practical, especially as regards its content and procedural aspects. Nevertheless, there remain a few fundamental conceptual lacunae. In particular, it is unclear to what extent the European Certificate of Succession can give rise to registration in the Member States' land registers, as well as how the European Certificate and the corresponding national instruments relate to each other. The aim of the research project is to develop a conceptual framework for these lacunae.