This study reviews some data and proposes some mathematical models that may be used to plan or design metropolitan wastewater reclamation and reuse systems. Specifically, optimization models have been developed for analyzing a wastewater reclamation project involving both water supply and water quality problems. The design problem examined involves the determination of least cost wastewater and water treatment plant capacities that satisfy water quantity and quality requirements at each water reuse site and also the quality constraints imposed on the waste receiving stream. In addition to developing a means of defining and evaluating alternative design for water reclamation and reuse systems that meet a variety of water quantity and quality requirements, the study also investigates the extent that water can be treated for reuse as an alternative in achieving water supply and pollution control objectives. (Modified author abstract)