Water pollution has existed for many years in Hong Kong, but the Government's strategy for pollution control is now beginning to take effect. The strategy includes planning legislation, and the provision of sewage-disposal systems. In the past, the main thrust has been against traditional pollutants measured by BOD, suspended solids and various nutrients, but as these are brought under control, attention will be given to the need to control toxic pollutants. The existing policy and legislation does not deal with toxic pollutants well, and past work on toxic substances in Hong;Kong has concentrated on individual chemicals. The Environmental Protection Department is now seeking to (a) develop ecotoxicological expertise to identify toxicant pathways in the environment, (b) introduce mater-quality objectives for toxic substances which it can monitor effectively and (c) improve standards for effluent control.