Organic contaminants, volatile organic compounds, and heavy metals pose long-term threats to natural ecosystems and human health. Particularly in the last decade, metal sulfide nanomaterials have piqued researchers' interest due to their outstanding physicochemical characteristics that make them amenable to modulation, as well as their qualitative and quantitative structure-activity relationship, proving them uniquely equipped for the enhancement of cost-effective environmental remediation technologies. Written by a team of internal experts, Metal Sulfide Nanomaterials for Environmental Applications accompanies its broad range of users on a journey that starts with fundamentals' understanding and leads to the presentation of the latest developments and possibilities of applied use, specifically for chemical detection/sensing and monitoring in air, soil, and water matrices as well as for chemical reaction engineering purposes (conversion, photocatalysis, adsorption) to facilitate removal of pollutants.