The rainy season is expected to have a serious impact on life-saving services and ongoing humanitarian aid in Cox’s Bazar. The pre-monsoon and monsoon will cause access constraints to sites in both Ukhia and Teknaf, as mud roads become impassable, footpaths slippery and earthen stairs and slopes become dangerous and potentially collapse. Shelters and facilities will be damaged and flooded. The overall impact is likely to be an increase in needs for the 671,000 refugees and a more challenging response environment. This note summarizes a longer document on the potential impact of pre-monsoon and monsoon rains in the Rohingya camps of Cox’s Bazar. Key priorities are: Highly unsanitary conditions (Damage to latrines and structures, contamination of water sources), Waterborne diseases, and Damage to shelters (resulting in exposure to the elements, displacement and overcrowding).