One way to become a permanent resident in the United States is through an offer of employment. Either the person wishing to come to the country can petition for a green card based on a job offer, or the employer can petition for an employee's green card using Form I-140. Those who are currently living outside of the country can become permanent residents through consular processing.
Consular processing involves the USICS coordinating with the Department of State to provide a visa when one becomes available. This assumes that the I-140 petition has been approved. Those who are living outside of the country can use Form I-485 to ask for an adjustment of their status to permanent resident. When submitting the I-485 form, it is a good idea to submit the approved Form I-140.
It is also advisable to submit the job offer received from an employer as well as two color photos. Medical records may also be necessary to increase the odds that a foreign worker's status will be adjusted. Form I-864 may also need to be submitted by the sponsor if the worker is working for a company that he or she owns or that a relative owns. Those applying for adjustment are also encouraged to submit any other information that supports their adjustment.
Those who wish to immigrate to the country may do so legally for a job opportunity. However, the proper paperwork must be filled out to ensure that the process is completed in a legal manner. Those who are working in the country illegally may be sent back to their home country immediately. Employment immigration attorneys may be helpful to both workers and employers wishing to find or provide opportunities to find work in the United States.
Source: USCIS, "Green Card through a Job Offer", October 09, 2014