Asylum policy is broadly governed by the Geneva Convention Relating to the Status of Refugees. The convention, which was adopted in 1951 to deal with the masses of displaced people following World War II, established that men and women who had "well founded fear of being persecuted for reasons of race, religion, nationality, membership of a particular social group or political opinion" could seek asylum. Those granted asylum cannot be returned to their countries of origin and must be granted the right to work.
The convention does not cover people who may have moved because of poor economic prospects, wars, or natural disasters. And while countries that have signed onto the convention have agreed to honor its principles, they establish their own laws to implement it. So, for example, many Western European countries now deny asylum to people who can prove they faced persecution at home but passed through "safe third countries" en route to their final destination. This is to clamp down on "asylum shopping," where asylees allegedly attempt to settle in countries that provide the best economic prospects or the most generous social benefits.