Conventional water based sanitation systems are neither ecologically nor economically sustainable. It was designed and built on the premise that human excreta are a waste; suitable only for disposal and that the environment is capable of assimilating this waste. This erroneous presumption has lead to severe crisis resulting from the use of ecologically mindless sanitation systems, particularly in the developing world. Over the last two decades there has been increasing interest in the approach of 'Ecological Sanitation' which is a sustainable closed-loop system of managing human waste. This approach is holistic and based on the underlying principle to close nutrient and water cycles with as less expenditure on material and energy as possible to contribute towards sustainable development. This work introduces the concepts and principles of ecological sanitation with main focus on the reuse aspects and technologies employed in the application of the nutrients found in human excreta in agriculture. This book will be useful in providing a comprehensive overview on ecological sanitation to town planners, agriculturists, eco-solution providers, researchers and other interested people.