This volume addresses the situation of water and wastewater management from a global angle, underpinned by selected case studies. Without doubt, water and wastewater management are among the greatest challenges of our century, and there is also no doubt that the challenges posed by climate change will become even greater. However, most efforts, especially in developing countries but also in the so-called developed countries, have been less than optimal or not optimal at all. In particular, there are still too many people who have to live without clean water and decent sanitation. Today, 2.2 billion people lack access to safely managed drinking water and wastewater, and 4.2 billion people lack safely managed sanitation services. The question, why this is so and why in many cases in developing countries, is discussed in this book among other urgent water and wastewater management issues. The publication of this book is the start of a book series that in more detail critically reviews, discusses, and analyzes the water and wastewater situation and management in different regions and countries worldwide.