The Pacific-Australia Climate Change Science and Adaptation Planning (PACCSAP) Water Security in Tuvalu project completed a comprehensive Cost Benefit Analysis (CBA) of potential water security interventions in Funafuti and Vaitupu, two of the major islands in Tuvalu. This poster shows the results of the water security cost benefit analysis project in Tuvalu. This publication was produced under the Pacific-Australia Climate Change Science Adaptation Planning (PACCSAP) programme.