We organised a focus session on Computational Materials Design at NWO Physics 2023 in Veldhoven. Computational materials design is a vital tool in materials physics research and is of ever growing importance. Combining state of the art computational materials modeling and characterization, with experimental testing and validation allows for new materials to be designed for specific applications. Directly probing and predicting the correlation between the atomic scale structure and a material’s properties gives us powerful tools with which to design next generation technologies, advancing our society. Computational materials design is typically an interplay between, physics, chemistry, biology, engineering, and materials science where the understanding of the underlying physical processes are becoming increasingly important to accurately predict and understand material properties and behavior. In this focus session, we brought together the Dutch computational materials modelling community focusing on density functional theory (DFT), molecular dynamics (MD), and multiscale modelling with talks on Taming the defects in halide perovskites: insights from multiscale simulations by Shuxia Tao from TU/e, In silico defect engineering to facilitate the design of functional materials by Jonathon Cottom from Leiden University, Modelling of Complex Energy Materials with Machine Learning by Nong Artrith from Utrecht University, and Multiscale materials design and modelling for electrochemical energy devices by Qiong Cai from the University of Surrey.