In its review of immigrant visa petitions, the U.S. Citizenship & Immigration Services (USCIS) weighs factors related to the ties the prospective immigrant has in the United States and the reasons why they want or need to come to live in this country. For example, a family immigration petition will not be approved unless the foreign national has immediate relatives such as a spouse, mother or father, child or sibling already living here as a citizen or green card holder. An employment immigration petition is more likely to receive approval if the applicant has a job offer in this country and is coming to fill a position that the local labor market can’t reasonably fill. Foreign nationals fleeing persecution in their home country may be granted an immigrant visa as refugees or asylees.