If you have obtained a job or have received a job offer, you may be eligible to live and work in the USA. Most employment petitions require a job offer and require that the employer petition for the worker.
As with family visa applications, Green Cards through a Job Offer are subject to annual quotas for certain categories according to preference categories; each country also has a set allotment of available visa slots. The wait time for processing employment based visa applications frequently stretches into many years. For example, work permit visa preference categories are limited to 140,000 per year. As of March 2012, there are 234,000 pending applications for employment based Green Cards.
Most employers petition for an employee using Form I-140, Petition for Alien Worker. You may apply for an Employment Authorization Document (EAD) by completing Form I-765, Application for Employment Authorization, if you have received an offer of work from an American employer. The EAD allows you to work legally in the United States for 12 months even without a Green Card and can be renewed if you are still working for an eligible employer.
If You Are Living Outside the United States, you can become a permanent resident through consular processing. Consular processing is when USCIS works with the Department of State to issue a visa on an approved Form I-140 petition when a visa is available.
If You Are Living in the United States, you can become a permanent resident through adjustment of status when living inside the United States. Once the I-140 is approved and a visa number is available, you can apply on Form I-485, Application to Register Permanent Residence or Adjust Status, to become a permanent resident.
Certain categories of individuals, such as au pairs and students from certain countries participating in pilot summer job programs may qualify for an Exchange Visitor Visa. Visitors traveling to the United States under the Exchange Visitor Visa cannot participate in the VWP. You may bring your spouse or dependent children along with you, however, you must also apply for an EAD if you wish to work while you are in the United States. The Exchange Visitor Visa is valid for the length of your employment or program. You must submit the following documentation to be eligible for an Exchange Visitor Visa.
You may also qualify for a temporary worker visa if you are an artist, athlete or entertainer, a researcher, a seasonal worker, participating in a cultural exchange program, or possess extraordinary talent in business, science or the arts.
If you are the spouse or dependent child of a worker assigned to the United States for diplomatic work, you may be eligible to work legally while you are in this country if your home country has a Bilateral Work Agreement or a de facto Work Arrangement with the United States.