In the Central and Eastern European Late Middle Palaeolithic, the variability of Neanderthals’ lithic technologies was complemented by an asymmetric tool type called Keilmesser. Its morphological characteristics and interpretation as tool in long-term use provides a unique archive for late Neanderthal behaviour. Assemblages from Buhlen, Balver Höhle, and Ramioul were analysed. A multidisciplinary combination of functional analysis with controlled experiments allowed for an evaluation of published interpretations and led to a blueprint for a holistic approach employing different methods and scales of analysis, opening room for discussing a new perspective on Keilmesser.