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.