Until 1974 responsibility for demand forecasting lay with a large number of mostly small water supply undertakings and sewerage and sewage disposal authorities. Only since 1974, when 10 large Water Authorities were created, has there been much interest in the formal modelling of water demands and discharges. However, progress is severely handicapped by the  shortage of information on how and where the water supplied is used. A lot of attention has been given to trend analysis, but it is becoming increasingly clear that these models are inadequate. Econometric analyses using time series data have some potential, but it seems that the future will see increasing emphasis on modelling the use of water within households and  within individual industries. Agricultural demands are relatively small and are unlikely to receive much attention. Sewerage, sewage treatment and effluent discharges have not received a great deal of attention either in modelling work in the past, but the increasing interest in environmental issues will probably result in greater effort being devoted to modelling the effects of discharges.