This open access book focuses on the importance of reducing pollution and protecting water resources for the health of people and the environment. Water is vital for life on Earth. The quality of the world's freshwater resources is deteriorating due to the rise in pollution levels, which puts the health of people and the environment at risk. Emerging pollutants, a new class called Contaminants of Emerging Concern, pose a global water quality challenge. The identification and implementation of appropriate regulatory, monitoring, prevention, and control measures are hindered by limited scientific understanding and knowledge about sources and pathways of emerging pollutants, their behaviour and fate in the environment, and potential human and ecosystem health risks. The book presents selected contributions to the UNESCO-IWRA Online Conference “Emerging Pollutants: Protecting Water Quality for the Health of People and the Environment,” held on 17–19 January 2023. It offers an extensive overview of current research findings on emerging pollutants in aquatic ecosystems, groundwater contamination, wastewater management and reuse, circular economy approaches to pollutant lifecycle management, and the prioritization of emerging pollutants in the hydro-cycle. Based on scientific evidence and policy-relevant research findings, the book’s concluding chapter highlights research and policy gaps, offering recommendations for strategic and practical ways to manage emerging pollutants towards sustainable water management in the face of global changes and evolving environmental threats. This book is a scientific output in the framework of UNESCO Intergovernmental Hydrological Programme’s Ninth Phase “Science for a Water-Secure World in a Changing Environment” (IHP-IX, 2022-2029) and UNESCO-IHP’s International Initiative on Water Quality (IIWQ) in collaboration with the International Water Resources Association (IWRA).