How Immigration Works

The 2000 census helped to make this chart of reported ancestries in the United States. A shaded color represents the biggest group found in that area. The variety of groups represented shows the many countries from which immigrants have come to the U.S.
Image courtesy United States Census Bureau

­The United States is commonly referred to as a nation of immigrants. From the Mayflower and Plymouth R­ock in the 17th century to Ellis Island and the Statue of Liberty in the 20th, the U.S. has many symbols of its strong immigrant tradition, one closely tied to the promises of the American dream -- justice, freedom, equal opportunity and the pursuit of happiness. The ideas of diversity, tolerance and multiculturalism have become hallmarks of American society because the United States has systems that admit, process and accommodate forei­gn immigrants. In all likelihood someone in your family tree immigrated to the U.S. within the last hundred years, and some of your friends, neighbors and co-workers may be immigrants. ­­

­But despite this long history and growing diversity, immigration remains a controversial­ subject in America. The questions of “who” and “how many” should be allowed into the country can be difficult to reconcile. At the extreme end of the debate stand nativists, who believe that the country should be closed to almost all immigrants. Others believe in a completely open society. But somewhere between these two sides is where most of the debate occurs. In this article, we’ll explore some aspects of this debate while also learning how the immigration process works, how government agencies manage immigration and what terms like “illegal alien” and “permanent resident” really mean. And although immigration is a global process that affects every country in the world, for the purposes of this article, we’ll focus on how immigration works in relation to the United States.


Immigration Basics

Image courtesy U.S. Department of Homeland Security

­Th­ere are many terms associated with immigration, and often some of them mean the same thing. First, let’s talk about the difference between immigration and emigration. Immigration refers to people moving into a country while emigration refers to someone leaving a country. For example, if Bruno is leaving Austria to move to the United States (we’ll assume that he has a visa already), then he is emigrating from Austria and immigrating to the U.S.

Now that we’ve made that distinction, let’s consider why people immigrate. The legend of the American dream promises a better life, but more specifically, people often come to the U.S. to pursue employment opportunities, to reunite with friends and family or to escape conflict or oppression in their home country -- also known as seeking asylum.


The United States Congress exercises control over immigration by passing legislation that determines immigration law. The Department of Homeland Security and the agencies under its control, such as the U.S. Citizenship and Immigration Service (formerly part of the INS) and U.S. Customs and Border Protection, manage the immigration process and enforce the laws enacted by Congress. The president is sometimes a vocal figure when it comes to immigration, but he can only make decisions regarding refugee policy.

Often, you’ll hear about “aliens” or “illegal aliens” present in the U.S. These are not beings from outer space. These terms are used to refer to someone who is present in the United States but is not a U.S. citizen or national. (A national is someone who owes allegiance to the U.S. but is not necessarily a citizen, such as a resident of American Samoa.) A resident alien is someone who is not a citizen or national but has the right to live and work in the U.S. A nonresident alien is not a citizen or national and has the right be in the U.S. but only for a limited period of time, such as with a travel visa. Often, your classification depends on where you are in the immigration process, which we’ll discuss later in the article.


How People Immigrate

A passport is an essential document for identifying yourself at a port-of-entry. Your visa will likely be pasted inside.
Photo courtesy stock.xpert

­T­he first step in immigration, no matter your age, employment status or country of origin, is to apply for a visa. For citizens of some foreign countries, visas are required just to travel to the U.S for vacation. A student visa is another type of nonimmigrant visa. Other visas are granted to people who come to the U.S to work temporarily, and these visas are often easier to get for those who are prominent in certain fields -- athletes, artists, entertainers, professors or business leaders.

If someone wants to move to the U.S., he or she has to first fill out an application for an immigrant visa for permanent residence and submit it to a U.S. Consulate in the country of origin. Once the application has been submitted and any necessary fees paid, the applicant has an interview with a consular officer, who asks questions about the applicant’s background and his or her plans for immigrating to the U.S. This officer then makes the decision whether or not to grant a visa.


Having a visa doesn’t guarantee entry into the U.S. It allows the holder to travel to a port-of-entry (i.e. an airport or land border) where an immigration inspector decides whether or not to let the visa holder into the country.

The type of visa available to a potential immigrant depends on a variety of factors, including:

  • the country of origin
  • what the person will do after immigrating to the U.S.
  • whether or not the immigrant has family members “sponsoring” him or her

In the next few sections, we’ll look at some different types of immigrant visas. As with much of the immigration process, figuring out which type of visa is best for you can be a confusing process, so if possible, talk with an immigration attorney or another expert. We’ll also provide some links at the end of the article to some useful reference sites.

Family Connection

If you have a relative who is a U.S. citizen or permanent resident, you can apply for one of the 480,000 visas available every year to immigrants seeking to join family members in the United States.

First, your relative must file an I-130 Petition for Alien Relative and provide proof of your relationship. The relative also has to prove by an Affidavit of Support that he or she can support you at 125 percent above the poverty line. The I-130 petition must then be approved by the United States Citizenship and Immigration Service (USCIS), and the relative will be notified when the petition is approved or denied.

If the petition is approved, the Department of State checks to see if an immigration visa number is available for you, the potential immigrant. If already inside the U.S., you can apply to have your status changed to lawful permanent resident after an immigrant visa number becomes available. If you’re outside the U.S. when a number becomes available, you must go to the U.S. consulate assigned to that area.

Obtaining one of the 480,000 visas available every year may one day lead to gaining U.S. citizenship.
Photo courtesy USCIS

Sponsorship rules vary for U.S. citizens and lawful permanent residents. A U.S. citizen can sponsor his or her spouse, child or, if the sponsor is at least 21, a sibling or parent. A lawful permanent resident can sponsor a spouse or unmarried son or daughter.

Provided they are at least 21, parents, spouses, and unmarried children of U.S. citizens don’t have to wait for an immigrant visa number after the USCIS approves the petition filed for them. According to the USCIS Web site, everyone else must wait for a visa number in this order:

  • First preference: Unmarried, adult (21 years or older) children of U.S. citizens
  • Second preference: Spouses of lawful permanent residents, their under-21 unmarried children, and unmarried children of lawful permanent residents
  • Third preference: married children of U.S. citizens
  • Fourth preference: siblings of adult U.S. citizens

Diversity Lottery Program

If you don’t have a relative living in the U.S., you may be able to qualify for the Diversity Lottery Program. This program hands out 55,000 visas each year to people emigrating from countries with low levels of immigration to the U.S. The State Department actually selects 110,000 people a year because many don’t complete the visa process. After 55,000 visas are issued or the fiscal year ends, the lottery is closed for that year. If you receive a visa this way, you can live and work permanently in the U.S. and bring your spouse and unmarried children who are under 21.

For information on which countries are eligible for the Diversity Lottery Program, check out the State Department’s Bureau of Consular Affairs Web site. Some countries may be eligible one year and ineligible in another, so it’s important to stay up to date.

Lawful permanent residents are granted permanent resident cards, also known as green cards.
Image courtesy Department of Homeland Security

Immigration through Employment

Employers can sponsor potential employees in order to bring them to the U.S. First, the employer must submit a labor certification request to the Department of Labor. After the certification request is granted, the employer must file a Petition for Alien Worker, to be considered by the USCIS. If the petition is approved, the applicant can then get an immigrant visa number from the State Department. If the applicant is inside the U.S., he or she must apply to adjust to permanent resident status. If outside the U.S., he or she must go to a U.S. consulate to finish the process.

Like with family sponsors, foreign nationals applying for work visas are ranked in several categories - EB-1 Priority Workers, EB-2 Professionals with advanced degrees or persons with exceptional ability, EB-3 Skilled or professional workers and EB-4 Special Immigrants. The USCIS Web site has more information about these categories.

This world map has been modified to show net immigration throughout the world. Countries appearing larger than their normal size experience higher levels of immigration.
Image courtesy © Copyright 2006 SASI Group (University of Sheffield) and Mark Newman (University of Michigan)

Immigration through Investment

Every year 10,000 investor visas are made available, 5,000 of them for people applying to a pilot program run through USCIS-designated “Regional Centers.” A Regional Center is an organization or agency, approved by the USCIS, that focuses on a geographical area and “seeks to promote economic growth through increased export sales, improved regional productivity, creation of new jobs, and increased domestic capital investment” [ref].

To get a visa through the program, an alien investor has to prove that he or she is making an investment in a commercial endeavor in an approved Regional Center and that 10 or more jobs will be created directly or indirectly by the project.

An investor can also get a visa by starting a business or by purchasing and restructuring an existing business so as to create a new commercial venture. Or, he or she can expand an existing business by 140 percent or retains all jobs in an existing business that was experiencing financial troubles. Other methods of qualification include investing $500,000 in a rural area or troubled business or $1,000,000 in some other venture.


Huddled Masses Yearning to Be Free

This map reflects destinations for refugees and internally displaced persons. South America, the Middle East, Southern Africa and Western Europe have some of the highest refugee populations.
Image courtesy © Copyright 2006 SASI Group (University of Sheffield) and Mark Newman (University of Michigan)


­In 1948 the Universal Declaration of Human Rights proclaimed the right of individuals “to seek and to enjoy in other countries asylum from persecution” [ref]. Asylum is a form of protection offered to people fleeing from persecution based on the following personal characteristics:


  • race
  • politics
  • nationality
  • religion
  • membership in a social group

According to the Refugee Act of 1980, anyone may apply for asylum, no matter his or her alien status.

Unlike other forms of immigration, asylum has no quotas or limits on number of visas -- the person requesting asylum, the asylee, simply has to demonstrate a “well-founded fear” of persecution in his or her home country. However, an asylum seeker must apply within one year of arriving in the U.S. or at a U.S. border or point-of-entry, and he or she cannot reapply for asylum if a previous application was denied by a judge. Changed circumstances can also affect asylum status -- for example, if there has been a regime change in the asylee’s country of origin that would make returning to the country more or less safe.

In some cases, an asylum seeker can be removed to a safe country with which the United States has an asylum agreement. If a person who is seeking asylum is in transit from Canada or seeks asylum at a border between the U.S. and Canada, he or she may be forced to seek asylum in Canada [ref].

Affirmative Asylum

Affirmative Asylum refers to someone who has arrived in the U.S. or at a port-of-entry and submitted an application for asylum to the USCIS “without delay” (within a year of arrival). After the application is filed, the asylee will have a non-adversarial interview with an asylum officer, usually within 45 days. In most cases, the asylum seeker isn’t detained and is free to live in the U.S. but not to work while his or her case is being considered.

If the request for asylum is not approved, the asylee is referred to an immigration judge at the Executive Office for Immigration Review. If the initial application is approved, the entire process can be completed within 60 days. If the application is referred to a judge, it can take up to six months to resolve the asylee’s case.

Defensive Asylum

If someone requests asylum to defend against being deported from the U.S., then he or she is said to be pursuing defensive asylum. Someone can end up in the defensive asylum process if he or she was referred to an immigration judge by an asylum officer who didn’t grant asylum. A person may also be placed in the defensive asylum process if put in removal proceedings because he or she was living undocumented in the U.S., violated his or her immigration status or was caught trying to enter the country without correct documentation but has a “credible fear of persecution or torture” [­ref].

With defensive asylum, immigration judges hear cases in an adversarial manner (meaning in a courtroom), and the U.S. government is represented by a lawyer. The immigration judge determines if the applicant is eligible for asylum. If the judge rules against asylum, he or she decides if the applicant can avoid removal through any other process or if the applicant must be removed from the U.S.

Expedited Removal

Anyone caught trying to enter the U.S. at a port-of-entry with improper or no documentation may be subject to expedited removal. Immigration officials are required to ask anyone who may be subject to expedited removal the following questions [ref]:

  • Why did you leave your home country or country of last residence?
  • Do you have any fear or concern about being returned to your home country or being removed from the United States?
  • Would you be harmed if you were returned to your home country or country of last residence?
  • Do you have any questions, or is there anything else you would like to add?

Anyone who asks for asylum is given the chance to speak to an asylum officer and will end up in the defensive asylum process if found to have a credible fear of persecution or torture in his or her home country. “Credible fear” is determined through an interview with an asylum officer. If the officer decides the asylum-seeker satisfies the credible fear standard, then the defensive asylum process begins. If the officer finds that the asylum-seeker doesn’t have a credible fear of persecution or torture, he or she can request a hearing before an immigration judge. If the judge determines that the asylum-seeker has a credible fear, then he or she enters the defensive asylum process (the judge’s decision can’t be appealed). Otherwise, the asylum-seeker will enter removal proceedings. Most people placed in defensive asylum are released. Some fend for themselves; others are taken care of by relatives or charitable organizations.

For more information about the asylum process, check out the USCIS Web site.



After the genocide in Rwanda in 1994, many refugees fled to camps such as this one, located in what's now known as the Democratic Republic of Congo.
Photo courtesy Centers for Disease Control and Prevention

­At the end of 2005, there were approximately 8,394,500 refugees in the world, compared with 9,543,500 at the start of the year, according to the UN High Commissioner for Refugees (UNHCR) [ref]. More than two million of these refugees were from Afghanistan.

The term refugee generally refers to someone who is outside his or her country and is fleeing persecution, though the president has the right to grant individuals refugee status. Every year the State Department submits a report to Congress with proposed refugee admissions and then the president works with Congress to determine the number of refugees who will be admitted in the upcoming year. For the 2005 fiscal year, the following numbers of refugees were admitted to the U.S. from these regions:


  • Africa - 20,000
  • East Asia - 13,000
  • Europe and Central Asia - 9,500
  • Latin America and the Caribbean - 5,000
  • Near East and South Asia - 2,500
  • “Reserve” - 20,000 (These can be used for specific groups in need or may go unused.)

Refugees may be eligible for resettlement in the U.S. if the UNHCR or the U.S. embassy refers them, or if they are members of other groups determined eligible by the U.S. government (see The Worldwide Priority System).

Like with asylum, a refugee has to prove that he or she has a “well-founded fear of persecution” and has not participated in the persecution of others. A refugee is not eligible for resettlement in the U.S. if he or she is already resettled in another country or holds dual citizenship. If a refugee is a relative of a U.S. citizen, he or she should apply for an immigrant visa.

A refugee may also be eligible for Temporary Protected Status (TPS). During the TPS period, a refugee may stay in the U.S. and apply for work authorization. At the moment, TPS is eligible to people from Burundi, El Salvador, Honduras, Liberia, Nicaragua, Somalia and Sudan. Temporary Protected Status does not lead to permanent resident status, and when the TPS designation is terminated, the refugee reverts to his or her pre-TPS immigration status. Because of this, a person who falls under TPS should pursue options for permanent resettlement before his or her TPS expires.


Illegal Immigration

Signs like this one can be found near the U.S.-Mexico border, warning drivers to watch for illegal immigrants running across the highway.
Photo courtesy stock.xpert

­Esti­mates vary significantly as to how many illegal immigrants are living in the U.S. Some experts claim seven million while others say as many as 20 million [ref]. Twelve million is a figure commonly used by news organizations, politicians and some think tanks like the nonpartisan Pew Hispanic Research Center ref. While the U.S. Border Patrol catches many people trying to sneak across the borders, others are smuggled into the U.S. through shipping containers or in vehicles crossing the border. Some Cubans board homemade rafts and try to navigate the 90 miles of water to south Florida. Other migrants risk dehydration, bad weather, difficult terrain and wild animals by trying to cross the long border between the U.S. and Mexico.

All of these methods are very dangerous, and every year people die trying to enter the U.S. Since a fence was erected in 1994 covering parts of the California-Mexico border, around 3,000 people have died trying to cross into southern Arizona.


Once in the U.S., many illegal immigrants meet up with friends or family, some of whom may be in the country legally. Although it is against the law to hire illegal immigrants, many employers do so anyway because illegal immigrants will often perform menial, low paying jobs that others don’t want to do, such as picking crops or janitorial work.

Although illegal immigrants often fill jobs that Americans don’t want, some people complain that illegal immigrants don’t pay taxes and frequently send their wages to friends and family in their home countries, rather than contributing to the local economy.

One potential solution that has been proposed is a “guest worker” program that would allow employers to hire a foreigner if no American could be found for a job. The foreigner would be allowed to work at the job for a set period -- perhaps three years -- and would be tracked through a federal system. The worker would likely have to pay some taxes while in the U.S., and certain incentives would be provided for the worker to return home after his or her guest worker pass expires. Possible incentives include offering retirement benefits that can only be obtained in the worker’s home country.

The Border

The United States’ borders are policed by the U.S. Customs and Border Protection (CBP). The CBP mainly guards against illegal immigration, smuggling of people, weapons and drugs, and insects or other pests that could damage agriculture. The Border Patrol guards more than 6,000 miles of land borders and 2,000 miles of coastal water, utilizing check points, aerial and ground vehicles and high tech surveillance equipment. The Border Patrol also allows an average of 1.2 million people to legally enter the United States every day and is responsible for collecting customs.

If the Border Patrol has thousands of employees and such sophisticated equipment, then why are we always hearing about “broken borders”? Well, first of all, they have a lot of area to cover. The U.S. has extremely long borders, and having a person there to cover every inch of the border is almost impossible. And, though they catch many people trying to sneak across the borders, thousands of people do manage to enter the United States illegally every year (500,000 by some estimates), which raises many concerns, including terrorism.

In September 2006, Congress passed a bill to build 700 miles of fencing along the Mexico border. Since 1994, the U.S. government has been building a fence along parts of the California-Mexico border, though that fence still isn’t finished. While the new fence is very ambitious, it may never be built. To build 700 miles of fencing would be extremely expensive -- estimates range from $4 to $8 billion for a physical fence, and a “virtual fence” that uses sophisticated surveillance technology could cost up to $37 billion! Besides the cost, there is potential damage to wildlife preserves, and the migratory paths of animals such as mountain lions, deer and coyotes would be disrupted. Also, several American Indian tribes have claims to land that the proposed fence would cross. Other opponents to the fence call it a “new Berlin Wall” and say that, for a country that owes much of its success to the contributions of immigrants, it’s the wrong message to send [ref].

Congress passed a bill to extend this fence to cover the entire U.S.-Mexico border, but the question remains of whether it will ever be built.
Photo courtesy stock.xpert

Some groups have decided that a border fence is important enough to them that they want to build it themselves. The Minutemen Civil Defense Corps, one of several civilian groups that "police" the border, has begun building a fence of its own along a 10-mile stretch of land in Arizona. As of November 2006, they had completed about a mile of their planned fence, relying on donations from the public to pay for materials.


Deportation and Amnesty

­A law passed in 1996 states that anyone who’s not a U.S. citizen and receives a jail sentence of a year or longer can be deported, or forcibly removed, from the U.S. This law was intended to crack down on some types of crime associated with an increase in illegal immigrants, such as gang violence and drug smuggling. However, since it was passed, some people have been deported for crimes they committed many years ago, even though they have served their time and become law-abiding citizens.

The Department of Homeland Security has also become more active in tracking down and deporting illegal immigrants since September 11, 2001. In some cases, problems with deportation can occur when the country of origin refuses to accept the person being deported.


If you or someone you know is facing deportation, contact an immigration attorney immediately.


Over the last two decades, many illegal immigrants have been saved from deportation by amnesty, a pardon for people who have broken immigration laws. Amnesty also allows illegal aliens to obtain permanent residency in the U.S.

Prior to 1986, amnesty was granted on a limited basis. The first large-scale amnesty was the 1986 Immigration Reform and Control Act, which gave amnesty to about 2.8 million illegal immigrants. Six other amnesties have followed, some targeting specific groups. The 1997 Nicaraguan Adjustment and Central American Relief Act gave amnesty to almost one million illegal aliens from Central America. In 1998, the Haitian refugee Immigration Fairness Act granted amnesty to 125,000 illegal aliens from Haiti, many of whom had suffered from the political turmoil and violence that had consumed their country.

Amnesty remains a controversial subject. Some critics believe it encourages people to immigrate illegally to the U.S. in the hopes of another large-scale amnesty. Supporters of amnesty say that, among other benefits, it helps by making illegal immigrants eligible for taxation and integrates them into society.


Ellis Island

The Statue of Liberty was a welcome sight for millions of immigrants on their way to Ellis Island with hopes of better lives in America.
Photo courtesy stock.xchng

­From 1892 to 1954, 12 million immigrants passed through Ellis Island on their way to better opportunities. Forty percent of America’s present population can trace their ancestry through this small island in New York harbor. Before becoming an immigration station, Ellis Island was at times a rich fishing area, a place where pirates were hanged, a weapons depot and a fort. Owned in the 1770s by Samuel Ellis, it was an important coastal defense site during the War of 1812.

After 1924, the immigration system began to shift towards how it is today. Potential immigrants applied for visas at U.S. consulates around the world, though many still used Ellis Island as their port-of-entry. Increasingly Ellis Island became used as a detention center and a training ground for the U.S. Coast Guard. It officially closed in 1954. Declared a national monument in 1965, Ellis Island has experienced extensive renovations and is now one of New York’s most popular tourist attractions. You can find its Web site here.


For more information on how immigration works and the history of U.S. immigration, check out the links on the next page. ­

Lots More Information

Related HowStuffWorks Articles

More Great Links

  • "U.S. Immigration Policy." 8/1998. Close Up Foundation.
  • "Glossary." U.S. Citizenship and Immigration Services. 3c6a7543f6d1a/?vgnextoid=b328194d3e88d010VgnVCM10000048f3d6 a1RCRD&vgnextchannel=b328194d3e88d010VgnVCM10000048f3d6a 1RCRD
  • "Guest Worker Program." United States Immigration Support.
  • "Illegal Immigration to the United States." United States Immigration Support.
  • "Immigrants to the U.S." U.S. Department of State: Bureau of Consular Affairs.
  • "Immigration." 6/5/2006. Cornell Law School.
  • "Glossary of Immigration Terms." Immigration Equality.
  • "Immigration Through a Family Member." U.S. Citizenship and Immigration Services. 14176543f6d1a/?vgnextoid=0775667706f7d010VgnVCM10000048f3d6 a1RCRD&vgnextchannel=4f719c7755cb9010VgnVCM10000045f3d6 a1RCRD
  • "Immigration Terms and Definitions Involving Aliens." United States Department of the Treasury: Internal Revenue Service.,,id=129236,00.html
  • "Inter-country Adoptions."U.S. Citizenship and Immigration Services.
  • "Legal Definition of Naturalized Citizen." Lectric Law Library.
  • "Definitions of Immigrant Status." 12/22/2004. Wisconsin Department of Health & Family Services.
  • "ABCs of Immigration - Expedited Removal." Siskind Susser Bland.
  • Becker, Jim. "Minuteman Corps Builds Its Own Border Fence." 10/30/2006. KOLD News 13.
  • Knickerbocker, Brad. "Illegal immigrants in the US: How many are there?" 5/16/2006. The Christian Science Monitor.
  • Robbins, Ted. "Q & A: Building a Barrier Along the Border with Mexico." 4/6/2006. National Public Radio.