The brickyard of Baden-Sooss, in the Austrian part of the Vienna Basin was selected as the stratotype of the Middle Miocene regional stage Badenian for the Central Paratethys. Stratigraphy and correlation are up-dated, and the present state of the art on fossil groups is shown. The stratotype belongs to the Upper Lagenidae Zone in a regional paleo-ecological zonation. For interregional correlation the section belongs to a part of calcareous nannoplankton Zone NN5 without Helicosphaera waltrans, to dinocyst Zone Cte, and in planktonic foraminiferal zonation by the occurrence of Orbulina suturalis to Zone M6, and to the middle part of the Langhian stage. The sediments of the so-called “Badener Tegel” are part of the Baden Formation, correlated with the Lanzhot Formation in the Czech and Slovak part of the basin. Deposition of the calcareous silty clays occurred at a water depth of around 200 m in a relatively warm, well-stratified water column. Re-deposition of fossiliferous coarser sediments from shallow regions occurs.