|Legal status of persons|
Immigration law, regarding foreign citizens, is related to nationality law, which governs the legal status of people, in matters such as citizenship. Immigration laws vary from country to country, as well as according to the political climate of the times, as sentiments may sway from the widely inclusive to the deeply exclusive of new immigrants.
Immigration law regarding the citizens of a country is regulated by international law. The United Nations International Covenant on Civil and Political Rights mandates that all countries allow entry to its own citizens.
Certain countries may maintain rather strict laws which regulate both the right of entry and internal rights, such as the duration of stay and the right to participate in government. Most countries have laws which designate a process for naturalization, by which immigrants may become citizens.
Immigration law in the USA 
The immigration laws in the United States have experienced uneven progress. During colonial times independent colonies created their immigration laws. The first attempt to naturalize foreigners was through the Naturalization Act of 1790. However many years later the Chinese Exclusion Act was passed to stop the immigration of Chinese people. The Emergency Quota Act of 1921 and the Immigration Act of 1924 put a quota on how many immigrants were permitted, based on nationality and previous influx years. The Immigration and Nationality Act of 1952 led to the creation of the Immigration and Naturalization Service.
Homeland Security, the Department of Justice, the Department of State, the Department of Labor, and the Department of Health and Human Services. Of the five, the Department of Homeland Security, which replaced the Immigration and Naturalization Service, enforces immigration laws and bestows benefits on aliens.  Immigration and Customs Enforcement, and Customs and Border Protection.
Every year, the Federal government conducts a Diversity Visa Lottery. The lottery grants citizens of other countries legal entry into the United States. However only those from countries "with low rates of immigration to the United States" are allowed to apply.
Presently there are two different types of US visas: one for people seeking to live in the US; termed Immigrant Visas, and the other for people coming for limited durations, termed Non-Immigrant Visas. The former visa has "per country-caps", and the latter does not. Most non-immigrant visas are for work purposes, and usually require an offer of employment from a US business. Other categories include student, family and tourist visas.
The United States allows more than 1 million aliens to become Legal Permanent Residents every year, which is more than any other country in the world. The United States also issues more Visas than any country in the world.
Control measures 
To control immigration, many countries set up customs at entry points. Some common location for entry points are airports and roads near the border. At the customs department, travel documents are inspected. Some required documents are a passport, an international certificate of vaccination and an onward ticket. Sometimes travelers are also required to declare or register the amount of money they are carrying.
Comparison of immigration visa categories by country 
This section is an attempt to classify and bring together information about immigration legislation on a number of countries with high immigration.
|Country||Separate article on Country's Immigration Law||Employer Sponsored Work Visa||Independent Work Visa||Businessman, Self-employed or Entrepreneur||Investor||Ph.D. or Scientist||Spouse||Asylum Seeker||By birth while both of parents are foreign nationals||Studying as a migration route||Illegal Migrant||Citizenship||Special arrangements|
|USA||United States nationality law||Through H1B lottery, many applicants failed to receive a settlement after 6 years and had to leave the country.||EB-1 Extraordinary Ability - for internationally recognized scientists, sportsman etc.||EB-5: you need to invest $500.000||PhDs are generally allowed to apply for an employer-independent EB2 visa||Available||After 5 years of permanent residence known as Green Card||Green Card Lottery|
|United Kingdom||British nationality law||Tier 2 - settlement (ILR) after 5 years. A limit on number of Tier 2 migrants per year introduced by new government which makes it very difficult to find an employer willing to sponsor the visa. Tier 2 Intra-company transfers do not lead to settlement (ILR).||(practically not available since April 2011) Tier 1 General - settlement (ILR) after 5 years. A limit on 1000 Tier 1 migrants per year introduced by new government. Besides that the migration legislation changes on average every six months which makes Britain not attractive for skilled migrants looking for a second nationality.||Tier 1 Entrepreneur||Tier 1 Investor||There is no specific category here but it is easier for universities (as opposed to businesses) to acquire a Tier 2 visa||ILR is provided after 2 years in marriage or partnership.||UK is a popular destination for asylum seekers. Due to high number of asylum seekers, the Asylum Tribunal seems to be very unlikely to recognize even very irresistible proofs for asylum grounds.||British citizenship can be obtained as a right for anybody who was born in Britain before 1994. After 1994, it can only be obtained by birth if at least one parent was settled there. It is also available as of right for people of whom one parent is a British citizen otherwise than by descent". All other classes of British Nationality do not confer right of abode in the UK to the holder.||Tier4 Full-time students used to be are allowed to work up to 20 hours a week, which is now changed to 10 hours. After 10 years of continuous presence in the country on residential visas ILR is provided (this is probably not valid any more). For those who graduated in the UK there is [Tier 1 Post Study Work]||After 15 years of continuous illegal but proven presence in the country ILR is provided.||Citizenship is provided after 1 year of Permanent residency. Permanent residency in the UK is known as settlement or "Indefinite Leave to Remain" (ILR).||EU citizens (temporary except Bulgaria and Romania), as created by the Treaty of Rome at 17 have the right to work, provide services or self-employment in the UK
Some commonwealth citizens have right of abode in the UK, which for most practical purposes gives them the same rights as British Citizens in the UK.
|Canada||Canadian nationality law||Official information||Available but Canada reduced the number of jobs in demands. E.g. software engineers are now unable to use this route.||Federal skilled worker|
|Australia||Australian nationality law||Available|
|New Zealand||New Zealand nationality law||Available|
|South Africa||South African nationality law||Quota Work Permit|
|Isle of Man||Similar to British Tier1 General, but does not lead to EU nationality||Similar to British Tier1 Entrepreneur, but does not lead to EU nationality|
|Hong Kong||General Employment Policy (GEP); will receive Right of Abode (ROA) in Hong Kong, after 7 years continuous ordinary residence in Hong Kong.||General Points Test (GPT)||Capital Investment Entrant Scheme (CIES); you need to invest HK$10 million except on real estate; will receive Right of Abode (ROA) in Hong Kong, after 7 years continuous ordinary residence in Hong Kong.||passing General Points Test (GPT) within Quality Migrant Admission Scheme (QMAS)||Person under 21 years of age born in Hong Kong of foreigner with HK Permanent ID Card, will receive Right of Abode (ROA) in Hong Kong, but not Chinese nationality.||Foreigner who is a Hong Kong Permanent ID Card holder may naturalise as Chinese national with HKSAR Passport, if applicant has settle in Hong Kong or Chinese territory, has near relatives of Chinese nationals, and other legitimate reasons.||Mainland China issued a daily quota of 150 One Way Permits to mainland Chinese for Hong Kong settlement; will receive Right of Abode (ROA) in Hong Kong, after 7 years continuous ordinary residence in Hong Kong; plus the right to apply for a HKSAR Passport.|
|India||Indian nationality law||After 12 years of residence (of which 1 year should be continuous)|
|Israel||Israeli nationality law||Not available||Law of Return|
|European Union||Citizenship of the European Union||Varies by member state||See Blue Card (European Union)|
|Austria||May be available in the future, called Rot-Weiß-Rot-Card|
|Cyprus||It is considered to be very unlikely to get nationality through work route||Not available|
|Czech Republic||Not available|
|Denmark||Available: Danish Green Card|
|Germany||Not available||There are programs for Continental Refugees and Repatriates but the rules are severely tightened to prevent as little new migrants as possible to benefit from them.|
|Luxembourg||Luxembourgian nationality law|
|Netherlands||Dutch nationality law|
|Romania||Special arrangements for citizens of Moldova|
|Norway||Norwegian nationality law||Min 4 years, see Norwegian nationality law#Naturalisation as a Norwegian citizen for more details.||Min 7 years, see Norwegian nationality law#Naturalisation as a Norwegian citizen for more details.||Citizens of other Nordic Council countries may naturalise after a two-year residence|
|Country||Employer Sponsored Work Visa||Independent Work Visa||Businessman, Self-employed or Entrepreneur||Investor||Ph.D. or Scientist||Spouse||Asylum Seeker||By birth||Studying as a migration route||Illegal Migrant||Citizenship||Special arrangements|
Details on immigration law of different countries 
|Country||Requirements and restrictions before settlement||Requirements and restrictions after settlement||Will resident visa holder dependant be allowed to work as well?||Is it possible to bring old parents once got settlement?||Is it guaranteed that immigration legislation would not be changed retrospectively and were there retrospective changes of immigration law previously?||Access to social benefits before settlement||Access to social benefits after settlement||Is it possible to deprive of earned citizenship? (apart from obvious reasons like proven deception in application to citizenship or terrorism)||Would the country require to surrender a previous citizenship(s) to apply for a citizenship of this country?||Would the country require to surrender its citizenship if its citizen applied for a citizenship of other country?|
|USA||No||No||No, but you will be required to pay taxes to US government regardless where the income is earned|
|United Kingdom||No more than 180 days spent overseas within 5 years, no more than 90 days per trip.||Settlement would be cancelled after certain number of days spent abroad||Yes, dependants will have a right to work||Theoretically you can bring a single parent if you are the only supporter. Many people had to do it through a court.||It has been changed retrospectively in the past and likely to change retrospectively in the future||No access to public funds.||Yes||Yes, for potentially unlimited number of reasons British nationality law#Deprivation of British nationality||No British nationality law#Dual nationality and dual citizenship||No British nationality law#Dual nationality and dual citizenship|
|Israel||||Yes, unless citizenship obtained by Law of Return|
|Norway Norwegian nationality law||Yes Norwegian nationality law#Loss of Norwegian citizenship||Yes Norwegian nationality law#Dual citizenship||Yes Norwegian nationality law#Dual citizenship|
Immigration regulation is the control of the people, and their numbers, who may enter a nation's sovereign territory. It applies both to persons seeking to live and work in a particular nation (or part of it) and tourists, persons on layover due to travel issues, and those wishing to study or otherwise make use of a country's facilities.
Immigration control of one form or another is imposed by most countries. It is an inherent right of a sovereign state.
See also 
- art 12(4)
- Proper, Emberson. Colonial Immigration Laws. Buffalo: William S Hein & Co., Inc., 2003. Print.
- "USCIS Home Page". Uscis.gov. Retrieved 2012-04-01.
- "ice.gov". ice.gov. Text ",,://www.ice.gov/ " ignored (help);
- "cbp.gov". cbp.gov. Retrieved 2012-04-01.
- "Diversity Lottery. USCIS - Diversity Lottery. 01 Oct 2008. US Citizen and Immigration Services. 6 May 2009".
- American Visa Bureau (2011-12-22). "US visas". Retrieved 2011-12-22.
- Schaefer, Kimberley. "DC Immigration Visa Bulletin". http://dcimmigrationattorneyblog.com/. Retrieved 6 August 2012.
- British Nationality Act 1981, s2(1)(a), subject to s14
- "Working temporarily in Canada". Cic.gc.ca. 2012-01-26. Retrieved 2012-04-01.
- "Immigrating to Canada". Cic.gc.ca. Retrieved 2012-04-01.
- "immi.gov.au". immi.gov.au. Retrieved 2012-04-01.
- FAQ New Amendments to the Rules for Capital Investment Entrant Scheme
- ; will receive Right of Abode (ROA) in Hong Kong, after 7 years continuous ordinary residence in Hong Kong.
- Verification of Eligibility for a Permanent Identity Card
- Application for Naturalisation as a Chinese National
- LCQ17: One-way Permit
- "Репатриация в Польшу. Новый закон о репатриации, права репатрианта в Польше - официальная информация" (in (Russian)). Wiza.polska.ru. Retrieved 2012-04-01.
- "Working in Sweden - Migrationsverket". Migrationsverket.se. 2011-12-22. Retrieved 2012-04-01.
- "Self-employed from countries outside the EU - Migrationsverket". Migrationsverket.se. 2012-02-21. Retrieved 2012-04-01.
- "Asylum seekers - Migrationsverket". Migrationsverket.se. 2011-05-19. Retrieved 2012-04-01.
- "Решение об отмене израильского гражданства и как с этим бороться". Pravo.israelinfo.ru. 2012-02-19. Retrieved 2012-04-01.
- Citizenship Laws of the World - the most comprehensive although a little bit outdated report by United States Office of Personnel Management Investigations Service PDF, copy: PDF
- American Immigration Law Foundation
- Immigration Equality's Immigration Law Glossary
- Inmigracion es:Inmigración
- US Citizen and Immigration Services
- Siskind's Immigration Bulletin
- Comparative Citizenship Analyses by European Union Observatory on Democracy (EUDO)
- Immigrations attorney Las Vegas