H2O. Is there any other molecule so vital, and so problematic, for people? Without water, agriculture vanishes and power plants grind to a halt. In other places, floods wreaks havoc. Millions of people every year die from drinking contaminated water. To help solve these challenges related to freshwater, scientists in many disciplines are applying new tools and techniques. They are trying to understand the impact of climate change on water quantity and quality, and predict future needs and threats. One recent development: making use of water—for drinking or industrial purposes—from sources that are otherwise considered unusable. Another emerging area is the ecological impact of activities related to the energy industry such as fracking or carbon sequestration. Other researchers are trying to increase the efficiency of farms and factories, the biggest consumers. This page is intended to provide an overview of research progress and current events across this wide ranging topic in Science and elsewhere.