This book gathers peer-reviewed contributions presented at the 5th International Conference on Calcined Clays for Sustainable Concrete (ICCCSC), held in Cape Town, South Africa, on February 4–6, 2026. Focusing on sustainable concrete technologies and applications, this book highlights the latest findings in this fast-growing field, addressing topics such as low-carbon cement production, performance evaluation, LC2 and LC3 technology, environmental efficiency, production and quality control, fresh and hardened concrete properties, service life modelling.