Mountains are the water towers of the world. However, they are not only an important source of water but also a source of key resources such as energy, minerals, and forest and agricultural products. They offer a multitude of recreational opportunities, and probably most importantly, serve as storehouses for biological diversity. Mountains provide the living space for about 10% of the world’s population. A much larger percentage of the population profits from the various services of mountains, most of which depend on water.