The Valley of Mexico, as well as many other regions in the world, is experiencing acute water shortages mainly due to population explosion, industrial development, and limited water resources. The major objectives of this study are to develop an empirical methodology which would aid the decision-makers in the selection of the best choice water reuse alternative and to present water reuse as a viable possibility for increasing water availability in the Valley. Industrial reuse, agricultural reuse, and ground water recharge are analyzed as the most viable alternatives. The Delphi technique is utilized in this study to determine the weights of several factors involved in the decision-making process towards the selection of the best alternative choice regarding water reuse. The analysis of the responses to the questionnaires indicated that the most important decision factors to be taken into account when establishing a water reuse program are in order of importance, public health, water quality requirements, public acceptance, operation and maintenance cost of a treatment system, water exchange, legal and institutional considerations, and capital cost of the treatment system. The results of this study show that the water supply, together with water reuse, will not be able to meet the demand unless a comprehensive water resources management program is conducted.