The Bureau of Pollution Control for the city of Atlanta, GA is responsible for four water pollution control plants. A hypermedia training system is being developed that is intended to be used by supervisory, operational, and maintenance personnel who control the water treatment facilities at the plants. The primary objective of this research effort is to develop an effective combination of text, figures, photographs, computer animations, and live video connected via hypertext links that motivates and communicates with the plant personnel. The methodology used to accomplish this goal is iterative design, which allows constant feedback from potential users of the system and emerging technologies and media to be gradually incorporated into the system. The development of a hypermedia training and reference system presents many problems in the successful integration of technology, information, and personnel. To support these needs, an audience description was formulated in order to understand the user characteristics. The basis of the information content of the system was obtained from an operations manual developed by plant management. Photographs, figures, and animations have been added to augment the text. An implementation schedule featuring iterative design with frequent behavioral evaluations was used to refine the content and incorporate appropriate visual aids. Alternative user interfaces, one based on the original manual and another based on a flow diagram of the processes at the plant, have been proposed to meet the needs of both inexperienced and experienced employees. The methodology for implementing the system and experiences in implementing it are discussed. The initial development of a text-based system was driven by the results of behavioral evaluations. Future developments will be based on behavioral evaluations and the use of visual technologies.