Water issues are inextricably linked to sustainable development since water must meet the needs of present and future generations. The reuse of wastewater is a socioeconomic challenge for the development of drinking water and wastewater services. It has the following advantages: it increases usable water resources, preserves natural resources and alleviates water shortages caused by climate change. Wastewater Reuse 2 provides a comprehensive and educational overview of the many ways wastewater can be reused, the variety of treatments, their performance, their conditions of use and how to combine them to give wastewater a new lease on life. Droughts are already a concern in many parts of the world; however, we now have new technologies to rely on.