Most foreign nationals who wish to travel to the U.S. for pleasure or business must first obtain a B-1/B-2 Visitor Visa (Others may be able to visit under the Visa Waiver Program.)
The most common categories of U.S. Visitor visa is listed below:
B-1 Visa For Business Visitors »
The B-1 Business Visitor Visa classification is for individuals who are seeking to come to the U.S. for temporary business activities. While employment is not allowed on the B-1 visa, the permissible activities do include attending meetings or seminars and conferences, meeting with prospective or current clients, exploring opportunities for setting up a business or participating in training.