The supply and use of bio-based products may yet shape the future, contributing to the achievement of broader objectives such as climate neutrality, circularity, and sustainability. Reducing dependency on non-renewable resources, and substituting fossil-based resources with biomass by way of a transition to a sustainable industrial – and especially chemical – sector, represent important challenges. To be able to understand what may be desirable pathways to a ‘green’ chemical sector, insights on the upcoming needs of biomass for the EU bio-based industry are required, together with information about its availability and the way it is produced. However, there is a lack of methodologies and quantitative tools capable of assessing and anticipating potential developments in the EU bio-based markets. To provide an early theoretical basis for the upcoming modelling of supply chains of the bio-based materials market, this short communication presents the conceptual framework underlying the BioMAT (Bio-based MATerials) model, developed in the course of the EU H2020 BioMonitor project.