Sudan - where the world's longest civil war has been fought for 21 years - is now the proving ground for customary law. The educated elite, particularly in the Arabized, Islamicized North, see customary law as backwards and incapable of coping with modernity, but the reality is that most Sudanese in the South adhere to it. In the context of the Comprehensive Peace Agreement (CPA) concluded in 2005 between the warring sides, customary law is being projected as a central element in the Southern identity for which the people fought and also as an important source of legislation, constitutionalism and the rule of law for the government of Southern Sudan.Although the shortcomings of customary law are recognised, it also enshrines the principles of universal human rights. Is it likely to finally bring peace to Sudan, what are the challenges that face those who want to turn aspirations into programs and strategies, and what implications does the Sudanese case have for other nations and groups? Written by the distinguished Sudanese jurist, scholar and diplomat Francis Deng, this important work is divided into two parts; the first defines customary law in context, and the second presents the views of leading legal and political figures on customary law and its place in the modern world.