Interfaces play a critical role in the behaviour of multi-phase and composite materials, governing mechanical response, transport phenomena, ageing, and failure. Advances in computational mechanics enable the detailed representation and analysis of interfaces across multiple scales in space and time, and under coupled physical processes [1,2]. This minisymposium will provide a platform for researchers to discuss novel methodologies and present their latest findings on the modeling, analysis, and simulation of interfaces, with emphasis on multi-scale and multi-physics applications. Contributions may address modeling concepts, discretization techniques, or both, applied to a broad range of interface-related problems. Topics of interest include, but are not limited to: • Computational homogenization of microstructured and multi-phase materials with interfaces • Dimensional reduction techniques for thin interphases • Coupled transport processes (diffusive, convective) across or along interfaces • Chemical reactions at interfaces • Interface contact under coupled mechanical, thermal, chemical, or electrical effects • Damage initiation, propagation, and failure at interfaces • Aging and degradation of interphases in multi-physics environments Applications of interest include, for example: • Battery electrode materials including novel solid state battery designs • Fuel cell membranes and electrode interfaces • Fiber-reinforced polymer–matrix composites • Grain boundary modeling • Geomechanical and geological interfaces in multi-phase porous media • Thin-film coatings and protective layers in harsh environments [1] D.R. Rollin, F. Larsson, K. Runesson and R. Jänicke, Variationally consistent homogenization of diffusion in particle composites with material interfaces using dual macroscale chemical potentials, Computational Mechanics (2025), doi.org/10.1007/s00466-025-02605-5. [2] M.G.D. Geers, V.G. Kouznetsova, K. Matous and J. Yvonnet, Homogenization methods and multiscale modelling: Nonlinear problems, in: Encyclopaedia of Computational Mechanics, second edition, Wiley, 2017.