This literature review covers over 70 documents related to standards, research, and use cases on the design of in-vehicle auditory alerts (IVAAs) for highway-rail grade crossings (HRGCs). Although standards exist for auditory warnings in vehicles and they have been used for years, there are only a few examples of their use at HRGCs. Furthermore, the limited research has concentrated on delivery systems of such messages, not on the specific message that should be provided at the HRGC. The research team recommends that the extensive body of knowledge and standards on IVAAs, identified as part of the review, should be used to design specific ones at the HRGCs for further testing and validation.