UN studies show that high-income, developed nations treat about 70 percent of their wastewater. However, in low-income developing nations, only 8 percent of wastewater undergoes any kind of treatment. Inadequate water treatment has serious consequences for both human health and the environment. The articles in this compendium provide a representative cross sample of both developing and developed nations’ water treatment facilities. Included are the following topics: Reclaimed water for irrigation reuse in developing countries Sludge-handling practices in Micronesia The removal of phthalate esters from Chinese water sources Disposal of domestic wastewater in Nigeria Ameba-enrichment in a South African water treatment plant Bioenergy from wastewater produced by a Brazilian meat-processing plant The presence of various pharmaceutical contaminants in the River Thames Wastewater recycling in Greece The impact on surface water from contaminants released from German water treatment plants A Canadian constructed wetland’s effectiveness for the removal of various contaminants from wastewater Accessing irrigation from treated wastewater in the United States The spacial distribution of fecal indicator bacteria in the groundwater beneath two American water treatment plants Detection of contamination from retinoid acid reception agonists in Japanese water treatment plants The editor, a respected international expert in the field, has selected investigations that offer essential information for ongoing research at the graduate and professional levels, as well as for environmental engineers and others responsible for choosing the most efficient water treatment technologies.