Preference System (Immigration Act of 1990)
The nine categories since fiscal year 1992 among which the family-sponsored and employment-based immigrant preference visas are distributed. The family-sponsored preferences are: 1) unmarried sons and daughters of U.S. citizens; 2) spouses, children, and unmarried sons and daughters of permanent resident aliens; 3) married sons and daughters of U.S. citizens; 4) brothers and sisters of U.S. citizens. The employment-based preferences are: 1) priority workers (persons of extraordinary ability, outstanding professors and researchers, and certain multinational executives and managers); 2) professionals with advanced degrees or aliens with exceptional ability; 3) skilled workers, professionals (without advanced degrees), and needed unskilled workers; 4) special immigrants; and 5) employment creation immigrants (investors).
Source: U.S. Citizenship and Immigration Services