There are several ways to obtain a work or business visa in the United States.
Non-Immigrant Visas (E-1, E-2, E-3, H-1B, H-2B, H-3, J-1, L-1, O, P, TN)
Immigrant Visas (EB-1, EB-2, EB-3)
Three steps to employment-based immigration:
1. PERM Labor Certification – assessment of whether or not there are qualified U.S. workers.
2. I-140 petition- employer petition for permanent foreign worker.
3. I-485 application for permanent residence (green card application). This step may include an application for advance parole (ability to leave the country) and employment authorization (ability to work while waiting) filings.