US immigration law allows for the immigration of foreigners to the United States based on relationship to a US citizen or legal permanent resident (green card holder). US citizens may sponsor their spouses, parents, children, brothers, and sisters. Legal permanent residents may petition for their spouses and children. The sponsored relative becomes eligible to have his or her immigrant visa or Green Card application processed only if the visa petition is approved. Family based immigration falls under two basic categories: unlimited and limited.
Immediate Relatives of US Citizens (IR): The spouse, widow(er) and unmarried children under 21 of a US citizen, and the parent of a US citizen who is 21 or older.
Family First Preference (F1): Unmarried sons and daughters of US citizens, and their children, if any. (23,400)
Family Second Preference (F2): Spouses, minor children, and unmarried sons and daughters (over age 20) of lawful permanent residents. (114,200) At least 77 percent of all visas available for this category will go to the spouses and children; the remainder will be allocated to unmarried sons and daughters.
Family Third Preference (F3): Married sons and daughters of US citizens, and their spouses and children. (23,400)
Family Fourth Preference (F4): Brothers and sisters of US citizens, and their spouses and children, provided the US citizens are at least 21 years of age.
The petitioning US citizen or legal permanent resident (green card holder) must submit an immigrant petition to the appropriate US Citizenship and Immigration Services (USCIS, formerly Immigration and Naturalization Service) office. Once the USCIS approves the petition, it will send the petitioner a notice of approval. The USCIS will also forward the approved petition to the National Visa Center of the US Department of State, which will contact the intending immigrant with further information.
Visa Ineligibility / Waiver
The immigration laws of the United States, in order to protect the health, welfare, and security of the United States, prohibit the issuance of a visa to certain applicants. Examples of applicants who must be refused visas are those who: have a communicable disease such as tuberculosis, have a dangerous physical or mental disorder, or are drug addicts; have committed serious criminal acts; are terrorists, subversives, members of a totalitarian party, or former Nazi war criminals; have used illegal means to enter the United States; or are ineligible for citizenship. Some former J1 exchange visitors must live abroad two years. Physicians who intend to practice medicine must pass a qualifying exam before receiving immigrant visas. If found to be ineligible, the consular officer will then advise the applicant if the law provides for some form of waiver.