Over one billion people lack access to safe drinking water worldwide. Polluted water isn't just dirty—it's deadly. Some 1.8 million people die every year of diarrheal diseases like cholera. Tens of millions of others are seriously sickened by a host of water-related ailments—many of which are easily preventable.

What can be done? Learn more about water problems in developing nations and explore possible solutions at Safe Drinking Water Is Essential, a Web site created by the Marian Koshland Science Museum of the National Academies.