Please check official U.S. government websites U.S. Embassy, U.S. Department of State, and Department of Homeland Security as well as the U.S. Visa Service. For an official determination of your situation, please prepare your documents and make an official application, for which you will be charged statutory fees, well in advance of your desired travel. The applicant bears full and sole responsibility for his/her application and any desired benefit.
U.S. Embassies, Consulates, and Dipolomatic Missions:
United States Visa Information Source
The Visa section of this website is all about U.S. visas for foreign citizens to travel to the U.S. Before traveling to the U.S., a citizen of a foreign country must generally obtain a nonimmigrant visa for temporary stay or an immigrant visa for permanent residence. The type of visa you will need is based on the purpose of your travel.
All participants and invited speakers/guests are required to make their own personal travel and visa arrangements