The objective of the paper is to provide an example of the application of personal computers for water quality management in Green Bay, Wis. The capabilities of the personal computer can help decision makers determine the level of remediation necessary to meet specified water quality goals through: development and use of complex mathematical models for water quality parameters, such as phosphorus and oxygen; organization and manipulation of the large amounts of field data required for model calibration and verification; simulation of a variety of management options aimed at cost effective improvement of water quality, and effective communication of technical concepts and management recommendations to decision makers and public interest groups.