Proper, Henderik A.Bjeković, MarijaMayr, Heinrich C.Rinderle-Ma, StefanieStrecker, Stefan2020-05-142020-05-142020978-3-88579-698-5https://dl.gi.de/handle/20.500.12116/33130In the context of information systems, and digital ecosystems at large, many different forms of systems modelling are used. This includes enterprise (architecture) modelling, business process modelling, ontology modelling and information modelling. The resulting models have come to play an important role during all stages of the life-cycle of digital (eco)systems, where we see such systems as being socio-technical systems involving a hybrid of human and digital actors, supported by (other) technologies. In our view, the key role of models also fuels the need for a more fundamental reflection on core aspects of modelling itself. In line with this, the goal of this paper is to explore some of the underlying fundamental challenges of modelling, and in doing so create awareness for, and initiate discussions on, the need for more foundational research into these challenges. The discussion of these challenges has been structured in terms of three clusters: the semiotic foundations, the essence of modelling, and the role of normative frames (such as modelling languages).enModellingSystems ModellingSemioticsText/Conference Paper1617-5468