Nothing is as clearly as it appears. Starting with a practical design for a natural water- recycle system in a village in the mountains of China, among the Miao minority community, this book investigates water-clearing systems and toilets both from a theoretical and prac¬tical approach. This book is a systematic, and scientific but very readable investigation of one of the most important topics in human civilization: the toilet. Surprisingly, they exists no literature that extensively and systemati¬cally discusses this topic. For this reason, this book aims to fill a serious gap in the scientific debate concerning cleaning water and the history and management of toilets, which represents one of the fundamental topics in human civilization. This analysis proposes a unique and extensive survey of the prob¬lematic issues related to the toilet from a his-torical, theoretical and technical standpoint of this fundamental aspect of human life. This book concludes with an illustration of a practical project that Prof. Paolo Vincenzo Genovese's team has been working on in a mountainous village in Guizhou Province in China, as a practical example of intervention in a small community.