This open access book gathers the proceedings of the 4th International Conference “Coordinating Engineering for Sustainability and Resilience” (CESARE) & Midterm Conference of CircularB “Implementation of Circular Economy in the Built Environment”, held in Timi?oara, Romania, on May 29-31, 2024, as part of the COST Action CA21103. The volume represents the state of the art of sustainability and resilience in modern and future built environment, constructions, and infrastructure, and includes topics such as structural materials and robustness, fire engineering, risk assessment, impact of climate change on the built environment, sustainable resilience of systems in the built environment, smart cities, circular economy, design strategies for product design, integration of renewable energy at building and small urban area scales, restoration & rehabilitation of historical buildings, sustainable infrastructures, wind energy structures, façade engineering, green buildings, and waste management.