The application process for unifying foreign-born persons with their family members in the U.S. involves numerous steps. Some of these are handled primarily by the U.S. citizen or permanent resident "petitioners" (often called "sponsors"); others are handled primarily by the intending immigrants themselves. Keep reading for an overview of the steps involved.
The U.S. citizen or permanent resident relative must start off the process, in order to advise U.S. Citizenship and Immigration Services (USCIS) that he or she wishes to sponsor an immigrant, and to prove that the family relationship really exists. This is usually done by mailing USCIS what's called a visa petition on USCIS Form I-130, with accompanying documents (such as a birth or marriage certificate and proof of U.S. citizenship or resident status) and the appropriate fee. The widow or abused spouse or child of a U.S. citizen, however, may self-petition, by filing Form I-360.
Once USCIS approves the petition, the case can proceed forward. In fact, in cases where the immigrant is an "immediate relative" (spouse, parent, or unmarried child under age 21 of a U.S. citizen), and the immigrant lives lawfully in the U.S., waiting for USCIS approval may not be necessary. The petitioner and immigrant beneficiary can do "one-step adjustment," as described in When an I-130 Can Be Filed at the Same Time as a Green Card Application.
Hopefully (after waiting several months or even years), USCIS will approve the visa petition. If USCIS denies it, the best bet is typically to figure out what the problem was and, if it's fixable, simply file a new petition.
Upon approval, USCIS will forward the immigrant's case file to the National Visa Center (NVC) for further processing.
In immediate relative cases, the NVC will immediately send some further paperwork to the petitioner (usually requesting proof of financial capacity to sponsor the immigrant, in the form of USCIS Form I-864) and then forward the case to the appropriate U.S. consulate in the immigrant's home country. In preference relative cases, however, another step gets added to the process, resulting in the case waiting at the NVC for years, as described next.
"Preference relatives," such as the spouses and children of green card holders and the married children or siblings of U.S. citizens, are not eligible for a green card right away. The reason is that the law has placed annual limits on the number that can be approved, and the supply never meets the high demand.
The waits are typically measured in years. The immigrant's place on the waiting list is secured by what's called a Priority Date; that is, the date when USCIS received the I-130 petition. See How Long Is the Wait for Your Priority Date to Become Current? for details.
Once the visa petition has been approved and a visa become available, the immigrant must submit an application for permanent residence. This is usually done by applying for an immigrant visa at a U.S. consulate outside the United States. The NVC and the consulate will communicate directly with the immigrant, sending various forms and documents to be filled out, as well as instructions on where to get the required medical examination done and an appointment for an in-person interview. (For details on that, see What the Medical Exam for a U.S. Green Card Involves.) This entire process is called "consular processing."
The other, less commonly used application procedure is called adjustment of status, and takes place at a USCIS office inside the United States. Again, only a limited number of immigrant applicants who are already living in the U.S. can apply for adjustment. What's important to know about this, however, is that once the I-130 is approved, an immigrant planning to adjust status should not wait for any official green light from USCIS. It's up to the immigrant to prepare the adjustment of status application and mail it to USCIS for further processing. USCIS will then call the immigrant in for a personal interview.
If the immigrant applies at a U.S. consulate, he or she will use an immigrant visa to enter the United States and claim permanent residence status. A green card will be sent some weeks later. If the immigrant applies in the U.S., permanent resident status will will be approved at or soon after the interview. Again, a green card will be sent within weeks.