This book gathers the latest advances, innovations, and applications in the field of optimization-driven architectural design, presented at the 1st International Conference on Digital Tools in Construction for Efficiency and Sustainability (DiGiCES2025), held in Amman, Jordan, on December 18–20, 2025, jointly with conferences OPT-iii2025, ADDOPT2025, and OPTARCH2025. It covers topics such as optimization software, evolutionary algorithms and swarm optimization, robust design optimization and reliability-based design optimization, optimization in micro- and nano-mechanics, multiscale and additive manufacturing, multidisciplinary and multiphysics design optimization, multiple criteria decision-making and optimization, generative and parametric design, parallel and distributed computing in optimization. Written by leading researchers and engineers, and selected by means of a rigorous international peer-review process, the contributions highlight numerous exciting ideas that will spur novel research directions and foster multidisciplinary collaborations.