As an employer (or prospective employer), if you want to sponsor a foreign national to become a permanent resident based on a permanent job offer, you and the foreign national need to go through a multi-step process.
In most cases, the process begins when the employer obtains an approved Labor Certification Application (LCA) from the U.S. Department of Labor (DOL). After the LCA has been approved by the DOL, the employer continues the process by filing Form I-140, Immigrant Petition for Alien Worker, on behalf of the foreign national with U.S. Citizenship and Immigration Services (USCIS).
If prior DOL certification is not required, the sponsoring process will start when you file a Form I-140 with USCIS. Form I-140 is available on the USCIS at www.uscis.gov. Sometimes, as discussed below, the foreign national can combine the Form I-140 with a permanent resident application. For information on all of the filing requirements and fees for a labor certification request with DOL, please visit that agency’s website at www.dol.gov.