Reactions at the water/solid interface are central to the development of sustain- able processes, from biomass upgrading to photo- and electrocatalysis. To gain atom- istic insight in these reactions, modelling approaches have been constantly improved over the past decade. Polarisable continuum models have considerably improved the description of charge separation and enabled a proper inclusion of the surface polari- sation in electrochemistry and photocatalysis. Micro-solvation has been used to probe the impact of H-bonding at the water/catalyst interface, a key ingredient to explain observed solvent effects in liquid heterogeneous catalysis. Last, considerable efforts have been dedicated to reach a full atomistic description of the water/liquid inter- face, allowing the evaluation of activation energies of catalytic reactions and catalyst decomposition. In this Viewpoint, we illustrate advantages and limitations of current methods and provide perspectives.