The evidence is mounting that climate change and variability will result in a significant decrease in available water resources throughout the Caribbean. Decreases will impact the supply-demand balance and water quality, and require the upgrading of water systems to meet future climate challenged operating conditions, including the effects of droughts and other extreme events. Evidenced-based planning that incorporates climate projections is needed to optimise adaptation investments in additional sources and systems. Optimisation under future climatic conditions will include increasing the efficiency of supply and distributed storage for greater resilience, and conserving water resources. Escalating power requirements will be offset through intensifying renewable energy use.