On Wednesday September 7 2016, M. Jaboyedoff was invited by Prof. G.B. Crosta to present a talk about: “Why do we need conceptual models for landslides?” by Jaboyedoff M., Abellan A., Blikra L., Derron M.-H., Jongmans D. & Locat J. within the session S 27: Mapping, monitoring and modelling: tools for landslide hazard assessment (Conveners and Chairpersons G.B. Crosta, Berti M., De Vita P., Frattini F.). The conceptual models are an important topic, it is fundamental to try to conceptualize methods to obtain such models. The session and discussions were very interesting and the congress very stimulating. Italian scientists are among the most active in landslides science in the world.