Small Island Developing States (SIDS) rely on small coastal aquifers that are fragile thin freshwater lenses that float on the underlying denser seawater and are recharged by rainfall. These coastal aquifers are at a higher risk of impact to water quality deterioration from threats including saltwater contamination from sea level rise, over abstraction, wave overtopping, loss of aquifer area through coastal erosion, and other impacts on water quality from inappropriate land-use activities. Climate change exacerbates these long-running threats to coastal aquifers through increased climate variability and climate extremes. The fragility of coastal fresh groundwater systems necessitates careful management and protection to ensure their long-term integrity and their role in climate change adaptation strategies. This project aims at improving the understanding, use, management and protection of coastal aquifers towards enhanced water security, in the context of a changing climate.