Modern computational mechanics generally rely on coupled problems. How to accurately and efficiently simulate systems where mechanics interacts with thermal, fluid, or material phenomena — and possibly across multiple scales simultaneously? This mini-symposium brings together researchers from computational mechanics, applied mathematics, and engineering around this shared challenge, with a consistent focus on couplings where mechanics plays a central role. Topics include fluid–structure interaction, thermo-mechanical coupling, contact and impact, multiscale modelling and computational homogenization, reduced-order approaches, heterogeneous and multiphase materials, as well as numerical coupling strategies (partitioned, monolithic, hybrid). Special attention is given to localized phenomena, validation and uncertainty quantification. Scalability toward high-performance computing environments is also of interest. The symposium aims to bridge methodological innovation and engineering relevance. Contributions may address both fundamental and applied aspects, from theoretical developments to industrial-scale simulations, including numerical methods.