The AASHTO Guide Specifications for LRFD Seismic Bridge Design, Third Edition (2023), cover the design and construction of new conventional bridges to resist the effects of earthquake motions, applying to bridges not classified as Critical or Recovery. The specifications are approved as an alternate to the seismic provisions of the AASHTO LRFD Bridge Design Specifications and use displacement-based design procedures rather than force-based methods. Sections set out general requirements and earthquake-resisting system requirements for higher seismic design categories, followed by analysis and design requirements by seismic design category. Further sections address analytical models and procedures and the design of foundations, abutments, structural steel components, and reinforced concrete components. Guidance and commentary cover demand modeling, capacity calculation, liquefaction effects, and risk-targeted ground motions. The specifications are intended for bridge designers working on structures in seismic regions.