"Four major principles underlie U.S. policy on permanent immigration: the reunification of families, the admission of immigrants with needed skills, the protection of refugees, and the diversity of admissions by country of origin. These principles are embodied in the Immigration and Nationality Act (INA). The INA specifies a complex set of numerical limits and preference categories that give priorities for permanent immigration reflecting these principles. Legal permanent residents (LPRs) refer to foreign nationals who live lawfully and permanently in the United States...Significant backlogs are due to the sheer volume of aliens eligible to immigrate to the United States. By the end of FY2004, U.S. Citizenship and Immigration Services (USCIS) reported 4.1 million immigrant petitions pending. Citizens and LPRs often wait several years for the relatives' petitions to be processed. After USCIS processes the petitions, the relatives of U.S. citizens and LPRs then wait for a visa to become available through the numerically limited categories. The brothers and sisters of U.S. citizens are now waiting 12 years. Unmarried adult sons and daughters of U.S. citizens who filed petitions five years ago are now eligible for visas. Prospective LPRs from the Philippines have the most substantial waiting times; consular officers are now considering the petitions of the brothers and sisters of U.S. citizens from the Philippines who filed more than 22 years ago."
CRS Report for Congress, RL32235
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