Clinoptilolite is a natural zeolite with exceptional adsorption capacity. Integrated into an appropriate technical Set-Lip it has been tested with raw-water mimicking the situation in emergencies where the requirement of safe drinking water has been critical for the public health. These results have been verified in practice in Chechenya and in Belgrade during the Balkan conflict. More recently the units have been used in Thailand in the aftermath of the tsunami and in Sudan. Future developments in treating water affected by radioactive fallout and arsenic are promising.