This collection of essays provides a state of the field on PFAS from a variety of perspectives within the water sector. Contributors include experts in industrial wastewater, municipal water management, and public health, with each contributor highlighting a different facet of the impact of PFAS in water and wastewater and providing guidance on the responses necessary to limit the chemicals' negative effects. The collection covers the current understanding of PFAS, the implications for human health, and the growing regulatory framework, as well as the various treatments available for water, wastewater, groundwater, biosolids, leachates and soil/sediments. Our understanding of PFAS, its effects, and the necessary responses is still evolving— this collection is not intended to answer all outstanding questions, but rather to further this critical conversation within and around the water sector.