Understanding subsurface resources requires linking pore-scale properties to reservoir-scale behaviour. This session highlights how advanced multi-scale rock and porous media characterisation, including scattering methods, CT imaging, NMR, laboratory testing, and field monitoring, can be integrated into upscaled thermo-hydro-mechanical-chemical-biological (THMCB) modelling. We invite contributions that connect detailed characterisation to constitutive models, constrain coupled process interactions, and reduce uncertainties in predicting subsurface performance. Applications may include CO₂ and H₂ storage, geothermal energy, waste disposal, and groundwater systems. Case studies that combine experimental data with modelling, as well as hybrid physics–data approaches, are particularly welcome. The session aims to bring together experimentalists, modellers, and practitioners to advance predictive tools for the safe and sustainable utilisation of geological resources.