The dispute over Western Sahara between Morocco and the Polisario Front evolved into full-scale war and after four decades remains unresolved. UN military observers separate the Polisario forces from Morocco's vast army but progress towards a settlement has been halting and the UN mission in Western Sahara is now among the longest running peace-keeping operations in the world.Here, Jensen provides a unique insider's account of the UN's involvement in Western Sahara, how the UN Settlement Plan was, after numerous obstacles, eventually put into operation and why it stalled. The Polisario is now adamant that only a referendum of self-determination with the option of independence is acceptable while Morocco offers a compromise settlement based on regional autonomy under Moroccan sovereignty. Both entrenched positions are constantly reaffirmed and unlikely to vary without major political change in the region.