A critical review is presented of operating practices, current problems, and research needs in the field of public water supply treatment technology. The study includes reports on resource, treatment, and distribution aspects. It (a) delineates the management aspects of problems of public water supplies which affect the production of high-quality potable water and its delivery to consumer taps, (b) analyzes and evaluates present operating practices, procedures and processes, (c) describes presently known procedures and processes not currently widely applied, and evaluates the effects if such were applied, (d) develops and defines recommendations for research which will provide the basic knowledge needed to improve process control, operation, management, and standards, and (e) provides a selective bibliography of technical literature concerned with quality aspects of public water supply sources, treatment, and distribution. (Author Modified Abstract)