As the Spanish were preparing to leave colonized Western Sahara in 1975, Morocco invaded, sparking a war with the Western Saharan Polisario Front. About 70% of Western Sahara was occupied by Morocco, which stations up to 140,000 soldiers in the territory, primarily along a 1700 kilometre long sand berm that is protected by one of the world's largest fields of landmines. In 1991, Morocco and the Polisario Front agreed to a truce ahead of a referendum on Western Sahara's future. However, Morocco has since refused to allow the referendum to take place, and has begun the extensive exploitation of Western Sahara's non-renewable natural resources. This has both highlighted the plight of the Saharawi people who live in refugee camps in Algeria and in occupied Western Sahara, and pushed the Polisario Front back to a position where it is openly canvassing for a return to war. This book was originally published as a special issue of Global Change, Peace and Security.