Climate change is projected to alter the global hydrologic cycle, causing increasing intensification and variability in precipitation. These changes will adversely impact water and sanitation coverage. The severity of these climate-related hazardous events on drinking water and sanitation systems will depend on a number of factors – the weather event itself, geographical region, and the sensitivity, resilience, and adaptive capacity of the water and sewage system that is affected. With continuing support from Wallace Genetics Foundation, a team of researchers from the Water Institute is developing a novel methodology to determine the vulnerability and preparedness of global drinking water systems to climate-related hazardous events. Vulnerability assessments for all countries will be finalized for drinking water and these methods will also be applied to score and rank the vulnerability of sanitation systems to climate change. This project will contribute to determining the projected impact of climate change on water and sanitation coverage.