Many developing countries are facing a severe problem of lack of availability of clean and pure drinking water. The world is facing challenges in meeting the rising demand of pure drinking water as the available freshwater sources are depleting due to droughts, increasing population, increasing water pollution. Clean water which is free from any organic, inorganic and biological impurity if essential for human health. Recently, nanomaterials have shown very much promise to remove organic, inorganic as well as biological impurities. This book deals with the recent developments of nanomaterials for the remediation of various organic and inorganic contaminants from water and wastewater.