A petrochemical plant in Taiwan, R.O.C., consumes a large amount of water daily, supplied by a local water company, in its cooling and manufacturing operations. The plant is located in an area with limited water and thus there are many water-related problems. A water resources management study conducted for the plant identified a unique opportunity for a major wastewater reclamation and reuse project. The water reuse project, when implemented, would not only solve many of the water-related problems of the plant, but also be economically profitable. A comprehensive pilot plant testing program demonstrated the technical and economic feasibility of the project. The technical as well as economic aspects of the project are summarized in this paper.