Abstract The unusual degree of interaction between service performance parameters and material selection for water lubricated contacts is developed. The importance of exploring the full range of variation in operation is stressed. The problems of corrosion, dirt and thin films associated with water lubricants in valves, bearings and seals are discussed. Examples are shown of some benefits gained through the use of water lubrication. The theory of elastohydrodynamic lubrication is shown to be of little use for water lubrication as a result of the negative and small positive (depending on temperature) pressure coefficient of viscosity. The properties of some successful water lubricated contact materials are reviewed with emphasis on water swell, abrasive wear resistance and minimum Hersey Variable values.