Pollutants in the form of heavy metals, fertilizers, detergents, and pesticides have seriously reduced the supply of pure drinking water and usable water. Gold metal has intriguing potential to deal with the water pollution problem, as recent research on several fronts is advancing the concept of nanoscale gold as the basis for cost-effective nanotechnology-based water treatment. Nano-gold has special properties, such as enhanced catalytic activity, visible surface plasmon resonance color changes, and chemical stability, that make it more useful than other materials. This Perspective article highlights the current use of gold nanoparticles for the efficient removal and the selective and sensitive detection of a variety of pollutants in water. The challenges in further developing nano-gold to address water contamination are discussed, which should stimulate future research into improved removal and detection of undesirable chemical compounds. (c) 2013 Society of Chemical Industry