Cross-laminated timber (CLT) consists of solid-sawn lumber boards laid up perpendicular to each other and bonded together to form large panels. The cross-lamination provides strength in both directions and allows large floor and wall spans. CLT is manufactured in controlled factory conditions providing consistent quality. Panels typically are 2 to 12 inches thick and up to 60 feet long, allowing large sections to be installed with minimal on-site assembly. CLT is increasingly used for mid-rise commercial and residential buildings, reducing construction time and environmental impact. Installation of CLT panels is similar to precast concrete; large panels are lifted into place and connected with bolts, welds, or specially designed connections. Connections must transfer loads effectively and accommodate the natural expansion and contraction of wood. Vibration during construction and under occupancy must be managed; CLT buildings can be more flexible than concrete or steel, and movement may be noticeable. Floor-to-floor connections are typically steel plates bolted or welded to embedded plates. Fire resistance of CLT depends on thickness; thicker panels provide adequate fire protection due to charring of outer layers. Acoustic performance is good due to mass; CLT provides sound reduction from adjacent spaces. Sustainability advantages of CLT include renewable material, lower embodied carbon than concrete or steel, and sequestered carbon in the building material. Structural performance of CLT has been validated by extensive testing and real-world performance. Fabrication precision from factory manufacturing ensures quality that may exceed site-built construction.