The 58 full papers included in thisbook were carefully reviewed and selected from 69 submissions. They were organized in topical sections as follows:Invited Papers; Numerical Methods: Analysis and Computations; Variational Analysis and Optimal Control; Space-Time Methods for PDE-Based Simulation and Optimization; Fractional Operators and Multi-Physics; Recent Advances in Computational and Applied Poromechanics; Mathematics and Algorithms for Predictive Digital Twins; Adaptive and Robust Domain Decomposition Methods; Applications of Metaheuristics to Large-Scale Problems; Large-Scale Models: from Life Sciences to Climate Research; HPCand HPDA: Algorithms and Applications; Numerical Solvers and Preconditioners for Differen tial Equations; Porous Media Flow and Transport; Fractional Differential Problems: Theoretical Aspects, Algorithms and Applications; and Contributed Papers.