Just to add to Jared's post and provide more info as to who Legal Permanent Resident Aliens are
Who are LPRAs?
LPRs are aliens who are granted permanent residence in the United States of America after petitioning the United States Citizenship and Immigration Services. Most people obtain an LPR status (ie a “green card”) using an employment based application process or a family based petition. Other less common routes include political asylum, adoption, refugee status and diversity visa lottery. With the employment-based petition the aliens must show that they qualify as (in decreasing order of preference/priority, probability of successful petition and visa number availability):
Workers of extraordinary ability in the sciences, arts, education, business or athletics
Outstanding professors or researchers
Multinational managers
Advanced degree professionals.
Workers who because of their exceptional ability in the sciences, arts, or business will substantially benefit prospectively the national economy, cultural or educational interests, or welfare of the United States
Professionals with bachelor’s degrees
Skilled workers
The process includes extensive background checks (10-fingerprint FBI criminal background checks, namechecks), reports of medical exams by a US civil surgeon ruling out tubercolosis, HIV, syphilis, gonorrhea, chancroid, granuloma inglunalis, lymphogranuloma venereum, hensen’s disease, mental disorders and use of controlled substances. This is followed by a complete vaccination record and redo of immunization in case of its absence (DtaP, IPV, MMR, Hib, HepB, Varicella, Meningococcus, Rotavirus, …). The petitions require extensive supporting evidence, often including a labor certification, evidence of scientific production, citation in the press, reference letters, citation scores, honors and awards, etc. The success rate oscillates around 60% for the first and second priority categories, less for other groups. The process include ~$1800 in federal fees plus lawyer fees (up to $6000).
