The Randall Lewis Center for Sustainability is pleased to present the State of Green: Greenprint Performance Report, Volume 15. As one of the largest global collections of transparent, verifiable, and comprehensive data about the environmental performance of buildings, this report provides aggregate benchmarks for the real estate industry on carbon, energy, waste, and water, and shows that despite a dizzying mix of market and other forces, whole-building energy consumption and carbon emissions reduced from 2022–2023. ULI Greenprint members in 2023 continued to reduce carbon emissions by 6.3% by reducing energy consumption and procuring new on-site and off-site sources of renewable energy. This volume also includes refrigerant data for the first time.