AASHTO NSMT-1 provides design and construction recommendations for strengthening existing reinforced concrete structures with titanium alloy bars (TiABs), using the near-surface mounted (NSM) construction method. The overall approach and organization of the guide are based on those presented in ACI 440.2R (ACI, 2017. See full citation below*). Design recommendations provided for shear and flexural strengthening are based on and adapted from the AASHTO LRFD Bridge Design Specifications . The recommendations are supported by experimental and analytical research, as well as field experiences that have demonstrated the application of TiABs for strengthening full-scale specimens typical of bridge girders. The available experimental evidence includes the influences of combined high-cycle fatigue and environmental durability on the structural performance of NSM-TiAB-strengthened girders.