Due to the scarcity of water in Egypt, the national water research plan of Egypt 2017–2037 focuses on using each drop of water including the rainfall water and flash floods water, in addition to the reuse of wastewater to close the gap between the demand and the supply. Springer published several books on the different aspects of water resources in Egypt without sufficient information on flash floods. Therefore, the idea of publishing a book on the flash floods comes to complete the picture of the water resources in Egypt. Why Egypt? Because it is a good example of arid countries located in MENA which are also almost arid regions. Consequently, the lessons learned from this book could be of great benefit for other countries in MENA regions particularly those in north Africa. This book is divided into 17 chapters, written by more than 25 researchers, scientists, and hydrologist experts from several institutions and more than one country, and have a good experience in the domain of water resources and particularly the topic of flash floods and rainfall. One goal of the book is to assess the flash floods environment, its hazards, risk, harvesting, utilization, and management in Egypt as a typical example of an arid country with water scarcity. The book also highlights some important experiences and successful case studies that reflect the present challenges and their possible solutions. The 17 chapters are presented in 5 parts in addition to the Introduction and Conclusions chapters. Part II is about Analysis and Design Aspects of the flash floods, while Part III is about the Recent Technologies for Investigating Flash Flood. The Environmental Approaches in Flash Flood are covered in Part IV. Part V discusses the Hazards, Risk, Harvesting, and Utilization of Flash Floods and Part VI is devoted to Prediction and Mitigation of Flash Flood in Egypt. The introduction chapter presents a summary of the technical elements of each chapter, while the conclusions chapter summarizes the most important conclusions and recommendations of the book in addition to presenting an update of the literature on flash floods.