Rapid population growth, limited water availability, climate variability and environmental pollution together cause a significant challenge to provide sufficient water to urban residents in a sustainable and effective way. Advanced water treatment technology can contribute to the solution of problems physically, but it may not ensure sustainable operation of water systems. The obstacles to sustainable water supply and services often are from non-technical problems such as low cost recovery, lack of sound pricing systems and sustainable financing for increasing service coverage. The financial and economic factors could be a large barrier to the operation of water systems. Through the case of Beijing, the book demonstrates how to use economics in managing urban water systems. The research employs the methods of cost benefit analysis, linear programming and rough set analysis. An integrated and quantitative analysis of the economic, environmental and social effects of water systems considering the viewpoints of different stakeholders is carried out, which is rare in the existing literature. The research shows that economics contributes to identifying the non-technical problems in water systems and can help decision makers to make choices that are consistent with the long-term well being of the community.