This chapter gives an overview of the famous Hunsrück-Schiefer fossil lagerstaette in the Lower Devonian of the Rheinisches Schiefergebirge (Germany). Fossil content, taphonomy and facies are briefly characterised and interpreted with respect to the palaeoenvironment. The echinoderm-arthropod association of the actual fossil lagerstaette occurs in the argillaceous shales of the middle Kaub Formation near Bundenbach (central Hunsrück). The excellent fossil preservation is due to rapid obrution of living biocoenoses by fine-grained turbidites on a moderately deep subtidal shelf and subsequent early pyritisation. Intercalated sandstone beds reflect shallower settings with arenaceous sedimentation and eurhenotypic benthic faunas. It is shown that the understanding of the term Hunsrück-Schiefer is heterogeneous up to the present day. We favour the concept of the lithostratigraphic Hunsrück-Schiefer Group restricted to the Sauerthal, Bornich and Kaub formations (Zlíchovian/lower Emsian) of the central and eastern Hunsrück, southern Middle Rhine and western Taunus areas. Biostratigraphic assignments of the Kaub Formation, on the one hand based on pelagic guide fossils (ammonoids, dacryoconarids), on the other hand based on neritic guide fossils (brachiopods), are still contradictory. The Hunsrück-Schiefer of the Mosel Synclinorium (Southeast Eifel region, central Middle Rhine region and southwestern Westerwald) is referred to as Wied Group, including Mayen, Leutesdorf, Augustenthal, Rüscheid and Isenburg formations. Brachiopods suggest a range of this succession from the middle Siegenian to lowermost Emsian (Ulmen). The term Hunsrück-Schiefer should not be used in a lithostratigraphic sense for the successions of the Mosel Synclinorium and the Salzig Anticline (northwestern Taunus) but may still be used in a facial or regional-geological sense (as Hunsrück-Schiefer facies).