Sustainability in construction is a priority for both academia and industry to reduce the carbon footprint of the built environment and thus combat climate change. Numerous approaches have been developed on how to tackle this issue, wherein the implementation of eco-efficient concrete is currently considered one of the most effective measures to be applied at the beginning of a building's life cycle. This edition of the Structural Engineering Document discusses key issues in selecting and incorporating eco-efficient waste materials capable of enhancing the sustainability of structural concrete in construction projects. The cost-efficiency of using recycled aggregates in structural concrete is shown by several world-renowned researchers. Critical evaluations and case studies further highlight the properties and performance of these materials and in various structural applications. Also, novel low-impact binding systems using industrial by-products showcase the importance of continuous research for technically viable alternatives capable of decreasing the huge dependency on ordinary Portland cement. The purpose of this document is to contribute to a broader understanding of the many possibilities for the development of a more sustainable structural concrete, thereby fostering resilient and sustainable construction practices to support the global commitment to environmental responsibility.