In August of 2017, the Federal Railroad Administration (FRA) held the fourth Grade Crossing Research Needs Workshop in St. Louis, MO. This workshop brought together national and international subject matter experts to collaborate, identify and prioritize specific research needs. The attendees included representatives of Federal, State, local, and international governments, as well as railroad, labor unions, academia, non-profit organizations, and consultants. Workshop participants identified and shared existing industry best practices and explored new grade crossing abatement and mitigation strategies that the rail industry can adopt to reduce the number of highway-rail grade crossing incidents and fatalities. Results will be documented in an FRA Technical Report.