Fluid-solid interaction (FSI) governs nature. From soft tissue modeling to lubrication technology, FSI problems in biomechanics and engineering are a major challenge in computational science towards understanding and emulating nature. This challenge is further intensified by the multiscale structure of materials and interfaces as well as by the finite configurational change (FCC) that a microstructure experiences under large deformations.The goal of this proposal is to conduct fundamental research on novel computational strategies for the modeling and analysis of multiscale FSI for materials and interfaces with FCC on all scales and homogenization as the core scale transition technique. The examples that will motivate and guide this research are potential future biological and industrial applications of the novel computational framework: (1) soft porous materials such as tissue scaffolds and articular cartilage that function together with pore-level fluids in order to facilitate organ regeneration and provide mechanical support, and (2) rough or textured compliant interfaces as in bearings and polymeric seals that deliver enhanced lubrication performance by increasing load-carrying capacity and decreasing energy consumption.The theoretical and computational basis of the envisioned research spans techniques from continuum and statistical mechanics. If successful, the major benefits of this research will be (i) a robust continuum FSI scheme based on the numerically efficient lattice Boltzmann method for the fluid coupled to the finite element method for the solid, which will constitute the basis of (ii) novel homogenization techniques that deliver a non-phenomenological description of advanced anisotropic porous media and lubrication theories, and which will ultimately yield to (iii) a multiscale framework through the application of recently developed isogeometric analysis techniques to macroscale porous media and lubrication interfaces.The overwhelming majority of the referenced research on which the present proposal rests has been conducted within the last 5-10 years, with major breakthroughs having been achieved only recently. Based on these recent advances, the vision in this proposal is to steer the macroscopic simulations of fluid-saturated materials and interfaces not with conventional phenomenological constitutive laws but solely through explicit microscopic FSI computations.