There is perhaps no region with a richer history or a more diverse ethnic, cultural and religious makeup than the Arab world. It is the cradle of civilization and birthplace of the world’s three major monotheistic religions. Despite their heterogeneity, the Arab countries are united by their common language and location in the largest arid zone of the world: the Sahara and African deserts and their contiguous semi-arid lands. The geographical area of the Arab world covers about 14 million km2 and spans two continents, covering a distance of 6,375 km from Rabat on the Atlantic to Muscat on the Arabian (Persian) Gulf (Bolbol and Fatheldin 2005) (Fig. 1.1). Consequently, the Arab populations, currently exceeding 300 million, representing 5% of the world populations, are mainly concentrated in the relatively fertile regions, particularly along the Nile River, in the valleys of the Euphrates and the Tigris, and along the coastal area of North Africa, Syria, Lebanon and Palestine/Israel. These four regions account for 84% of the Arab populations and only 54% of their income. The GCC countries (Gulf Co-operation Council), comprising Saudi Arabia, Kuwait, United Arab Emirates, Qatar, Bahrain and Oman, have about 45% of the income but only 10% of the Arab populations (Grissa 1994). With two thirds of the Arab countries producing oil, there is little doubt that it is the single most important factor in the region’s economic development (Raffer 2007).