New guide specifications on Load and Resistance Factor (LRFD) design (LRFD) and construction of road tunnels have been published by the American Association of State Highway Transportation Officials (AASHTO). The LRFD Tunnel Design and Construction Guide Specifications, available on the AASHTO website, is the result of a five-year research effort by WSP USA performed under a task order from the National Cooperative Highway Research Program (NCHRP).