Escalating violence in Myanmar's Rakhine State forced nearly 1 million Rohingya to flee to safety in refugee camps in neighboring Bangladesh. The massive increase in population exceeded the capacity of the existing refugee camps, forcing many of the new arrivals to live in makeshift shelters along roadways and steeply sloping hillsides that had been stripped of vegetation. These makeshift shelters are largely at risk from flooding and landslides in the upcoming monsoon and cyclone season. CRS and Caritas Bangladesh leveraged Collector to map as a replacement for hand-drawn paper maps to record these makeshift shelters and the number of inhabitants. This was supported by the availability of up to date imagery obtained from UAVs. ArcGIS desktop was used to assess the vulnerability of the refugee shelters to flooding and mudslides. For more information, please visit: https://www.esri.com/en-us/industries/sustainability/segments/sustainable-development