ABSTRACT: This paper considers the susceptibility of groundwater in England and Wales to nitrate pollution from agriculture. It considers the state of contamination, methods for assessment and means for protection. Voluntary controls for farmers are set out in the 'Code of Good Agricultural Practice' and mandatory measures apply under the Nitrate Directive Action Plan. Restrictions for previously established 'Nitrate Sensitive Areas' have improved groundwater quality in some cases. Subsequently, 68 Nitrate Vulnerable Zones (NVZ) were established under the Directive. The extent of Zones is being reviewed, which may result in the designation of vulnerable zones across most of England in order to protect both surface water and groundwater resources. A comprehensive review of groundwater monitoring is also underway, since current assessment of groundwater quality in England and Wales relies heavily on measurements at public supply boreholes. Geostatistical methods are also being developed to help assess the spread of nitrate contamination.