immigration policy

immigration policy is any policy of a state that affects the transit of persons across its borders, but especially those that intend to work and to remain in the country. Immigration policies can range from allowing no migration at all to allowing most types of migration, such as free immigration.
Immigration policy is often closely related to other policies:
Tax, tariff and trade rules that determine what goods migrants may bring with them, what services they may perform while temporarily in the country, etc., and who is allowed to remain, e.g. the European Union has few immigration restrictions within it if any. any citizen or resident of any of the signatory nations (with the possible exception of a few new member states) may move and seek work anywhere within the E.U. and there is nothing that member states can do to stop it without leaving the E.U. or renegotiating the treaty.
Investment policy that permits wealthy immigrants to invest in businesses in exchange for favorable treatment, early issuance of passports and permanent resident status.
Agricultural policy that may make exemptions for migrant farm workers, who typically enter a country only for the harvest season and then return home to a developing nation (such as Mexico or Jamaica which often send such workers to US and Canada respectively).
Overcrowding which can be blamed for the spread of Tuberculosis or a house price boom
Birth rates which are low in developed nations
An important aspect of immigration policy is the treatment of refugees, more or less helpless or stateless people who throw themselves on the mercy of the state they enter, seeking refuge from poor treatment in their country of origin.
With the rise of terrorism worldwide, another major concern is the national security of nations that let people cross borders. The belief is that terrorists can come from overseas. Another threat comes from terrorists originating from within a country, also known as "home grown terrorism," in which information on the Internet or other media can reach citizens within a country[1]. These concerns often lead to intrusive security searches and tighter visa requirements, which can discourage immigration, temporary visitors, and even movement within countries or birth within countries. Censorship of the Internet is also possible with Internet filters available that block terrorist sites or hate sites in general[2].
There is often pressure on nations to loosen immigration policy or inspections to enable tourism and relocation of businesses to a country, from a destabilized region.