Availability of clean water is a serious problem, especially in developing countries. Therefore, there is demand of low cost treatment for water purification. The use of natural coagulant like Moringa oleifera for the water treatment is the best low cost treatment method useful for society. In the present book the evaluation of Moringa oleifera seeds as a natural absorbent and antimicrobial agent for drinking water treatment was studied. Moringa oleifera, native to India, grows in the tropical and subtropical regions of the world. It is commonly known as 'drumstick tree'. Moringa oleifera seeds possess effective coagulation properties and they are non toxic to humans or animals and also biodegradable. These seeds contain proteins that have active coagulation properties and are being used for turbidity removal in many countries. The use of the local Moringa seeds for clarification is therefore useful in the purification of drinking water in developing countries, than other chemicals used. This book evaluates Moringa oleifera seeds as a water purifier and shows that it would be possible to develop an economical and an environmentally safe method of water purification