There have been many new advances with biosolids beyond land application of Class A and/or B biosolids (e.g., energy from biosolids, high-quality or exceptional-quality biosolids, etc.). Despite the research gathered to support the safety of Class A and/or B biosolids, there are still questions regarding the safety and technical aspects of biosolids land application. Recognizing that all regulations intended to protect public health and the environment must always be kept current with new science, and in response to current issues, there is an urgent need to identify and perform critical research to ensure regulations are up to date. The Water Research Foundation held a Biosolids Research Summit to define a roadmap and comprehensive, multi-year research agenda for such research. The final project report describes the development, approach, and outcomes of the Summit. Published in 2020.