Abstract
This chapter presents the advances in sanitation for developing countries as well as the needs in terms of goals, standards, technology, and policy. To understand why a special chapter for low-income areas is needed, it describes the main types of pollutants, their origins, and treatment options. As part of the text and to face the requirements for poor rural and urban areas and water-scarce regions, basic sanitation, wastewater treatment, and water reuse alternatives are described with emphasis on their constraints and limitations for developing countries. Some aspects concerning the development of policies, costs, and funding to fulfill the Millennium Development Goals are also included. The importance of developing innovative solutions that can be sustainable, affordable, and progressively implemented is discussed.