The primary purpose of Drinking Water Objectives is to protect public health. Water intended for human consumption should not contain disease-causing organisms or hazardous concentrations of toxic chemicals or radioactive parameters. Water should be aesthetically acceptable. Taste, odour, turbidity and colour are parameters that, when controlled, result in water which is clear, colourless and without objectionable or unpleasant taste. Other aspects of water quality such as corrosiveness, tendency to form incrustations and excessive soap consumption should be controlled on the basis of economic considerations because of their effects on the distribution system and/or the intended domestic and industrial use of the water. Parameters and their associated objectives are listed alphabetically in Tables 1 through 4. A brief description is provided for each parameter in Appendix A. Some parameters which do not have specific objectives are listed because there is an ideal range for them in terms of water treatment plant operation or aesthetic water quality. One section is devoted to sampling protocol, examination of drinking water supplies, and the recommended corrective actions to be taken when an objective level is exceeded. A summary of water disinfection procedures is outlined in Appendix B.