Today is World Water Day, and this year’s theme is “valuing water”. Water in the Peruvian Andes is an increasingly precious resource, with the continual retreat of the high mountain glaciers forcing communities downstream to think about how to adapt to the challenge of peak water, the point at which water production reaches its maximum before continually declining (in this case due to glacier response to a warming climate). While water quantity is threatened, so too is water quality, with contamination, both natural and anthropogenic in origin, compounding issues around water availability and security. Water in the Andes poses not only a threat to water resources, and inextricable links with food and energy security, but also poses a threat in the form of natural hazard. As the glaciers retreat they contribute to the downstream growth of glacial lakes, dammed by often unstable glacial sediments and dead ice. These natural dams can fail, leading to rapid flooding downstream, sometimes with tragic consequences. Yet while water is in many ways a threat in this region, it is also central to Andean culture and livelihoods. To explore how we value water, we need look no further than Peru.