Commencing with a summary of the current status, importance and productivity of natural wetlands the contribution of wetland ecological functions to sustaining vital ecosystem services is then reviewed. Provisioning services, notably fish and water for irrigation or domestic and industrial purposes constitute important benefits derived by humanity from wetlands, whilst recognition is growing that supporting, regulating and cultural services supported by wetlands are critical for sustaining social-economic systems and ensuring human well-being. Examples of wetland ecosystem services contributing to water and food security are highlighted and likely consequences resulting from disruption to stocks and flows of these services discussed. Wetlands are vulnerable to a range of anthropogenic pressures, notably land-use change, disruption to regional hydrological regimes owing to abstraction and impoundment, pollution and excessive nutrient loading, invasive species introduction and overexploitation of biomass, plants and animals.