Sodium tripolyphosphate (STPP) is an important ingredient of many detergents. The use of STPP has been associated with the environmental problem of “eutrophication”, the increase of nutrient levels in water, which can lead to the formation of large masses of algae or blooms which are unsightly, cause slow moving water to be turbid, and may be toxic. This paper considers policies to reduce the use of STPP in detergents and assesses their success in reducing eutrophication together with the impact on the phosphate industry. The extent of eutrophication has been reduced, but there is still an ecological problem in many areas. Policy directed specifically at detergent phosphates has now been effectively made redundant by the EU requirement to install tertiary treatment plant. While the phosphate industry has experienced a considerable reduction in demand and has consequently contracted, it can be expected to stabilise. Policy on phosphorus will continue to evolve, from the current emphasis on implementing the EU Directive on Urban Waste Water Treatment to dealing with the consequences of this – sludge – and addressing the other main source of phosphorus – agriculture.