To work temporarily in the U.S., the most common route is often through an employer-sponsored nonimmigrant visa. Your U.S. employer must completely file a petition at USCIS solely on your own behalf. Some nonimmigrant work visas, such as H-1B for specialized jobs, L-1 for employees moved within a company, or O-1 for people of extraordinary talent, have particular requirements that often demand verification of your skills. You may reside and also be employed in the U.S. for good if eligible for a work visa. Immigrant visas based on employment are in five preference groups (EB-1 up to EB-5), each having special requirements. The Permanent Workers webpage offers more details for clarification. For people outside of the U.S., you generally must apply for a visa by way of the Department of State (DOS), unless likewise exempted. USCIS must always approve the employer petition before you can apply for the visa at any consulate. After the approval, you may enter into the U.S. and begin working, subject to CBP’s authorization. If you’re already located in the U.S. under a particular nonimmigrant status that really doesn’t allow work, you can then apply for just a change of status or an adjustment of status to a certain category that permits employment. In some specific cases, for example, those involving extraordinary ability visas (EB-1A) or treaty investor visas (E-1/E-2), you may self-petition. You still may do so without having an employer. In the U.S., you can also apply for an Employment Authorization Document (EAD) using Form I-765 if you’re within, which grants broad authorization to work based upon your current status and pending permanent residency application. You must fully comply with each and every one of the terms of your employment authorization, as well as you should do so in order to avoid certain risks of removal or denial of re-entry.