Public opinion in Belgium recently began to question and criticize the relevance of its current notariate. The notary's prominent position in recording and authenticating agreements among individuals is thus at stake. Notaries nowadays are no longer considered as self-evident and, moreover, this research project argues that they have never been so throughout the course of their history. However, historiography into late medieval voluntary jurisdiction within the former Southern Low Countries too often and wrongly overestimated the importance of public notaries. In doing so, it basically minimized the complex legal reality of medieval society in these territories which at the time was strongly determined by regional and local customs. From a comparative approach and a novel multi-layered conceptual framework, this research considers the relationship between notaries and several indigenous alternatives for voluntary jurisdiction. Particularly in regard to the counties of Hainaut and Flanders, two historical principalities with very divergent socio-economic structures, it will establish a more nuanced and fine-grained understanding of how multiple intermediaries co-existed and balanced each other in their mutual competition as neutral recording instances for private legal transactions. Additionally, this project will offer scientifically substantiated arguments to the ongoing discussion about the added value of notarial services today.