• A Hybrid Conference – In-Person and Virtual Presentations
  • Technical Conference:  24 – 28 March 2024
  • Exhibition: 26 – 28 March 2024
  • San Diego Convention Center, San Diego, California, USA

Visas and Letters of Invitation

Letters of Invitation

Complete the Request Form Now

Apply for Your Visa Now

Begin the visa application process now! We strongly encourage you to apply for your visa at least six months prior to the meeting.  Start the process by requesting a letter of invitation, and reviewing visa requirements to enter the United States online.

A citizen of a foreign country who seeks to enter the United States generally must first obtain a U.S. visa, which is placed in the traveler’s passport, a travel document issued by the traveler’s country of citizenship.

Certain international travelers may be eligible to travel to the United States without a visa if they meet the requirements for visa-free travel. The visa section of the website in the above link is all about U.S. visas for foreign citizens to travel to the United States.

How Can I Use a Visa to Enter the United States?
Having a U.S. visa allows you to travel to a port of entry, airport or land border crossing, and request permission of the Department of Homeland Security (DHS), Customs and Border Protection (CBP) inspector to enter the United States. While having a visa does not guarantee entry to the United States, it does indicate a consular officer at a U.S. Embassy or Consulate abroad has determined you are eligible to seek entry for that specific purpose. DHS/CBP inspectors, guardians of the nation’s borders, are responsible for admission of travelers to the United States, for a specified status and period of time. DHS also has responsibility for immigration matters while you are present in the United States.
 
What Types of Visas Are There?

The purpose of your intended travel and other facts will determine what type of visa is required under U.S. immigration law. As a visa applicant, you will need to establish that you meet all requirements to receive the category of visa for which you are applying. When you apply at a U.S embassy or consulate, a consular officer will determine based on laws, whether you are eligible to receive a visa, and if so, which visa category is appropriate.

There are two main categories of U.S. visas:

Nonimmigrant visas – For travel to the United States on a temporary basis. Learn more.
Immigrant visas – For travel to live permanently in the United States. Learn more.

ESTA is an automated system that determines the eligibility of visitors to travel to the United States under the Visa Waiver Program (VWP). Authorization via ESTA does not determine whether a traveler is admissible to the United States. U.S. Customs and Border Protection officers determine admissibility upon travelers’ arrival. The ESTA application collects biographic information and answers to VWP eligibility questions. ESTA applications may be submitted at any time prior to travel, though it is recommended that travelers apply as soon as they begin preparing travel plans or prior to purchasing airline tickets.

 However, the following categories of travelers are no longer eligible to travel or be admitted to the United States under the Visa Waiver Program, and will need to apply for, and go through the standard Visa application process:

  • Nationals of VWP countries who have traveled or been present in Iran, Iraq, Sudan, or Syria on or after March 1, 2011 (with limited exceptions)
  • Nationals of VWP countries who are also nationals of Iran, Iraq, Sudan, or Syria. (Travelers who are known to fall into the dual national category noted above should have received notice via email on or about January 21, 2016 that their current ESTA is no longer valid). 
These restrictions do not apply to VWP travelers whose presence in Iraq, Syria, Iran, or Sudan was to perform military service in the armed forces of a program country, or in order to carry out official duties as a full-time employee of the government of a program country. These military and official government services exceptions, however, do not apply to the dual national restriction.
 
OFC Management provides the above information to help foreign travelers understand the process and requirements of obtaining visas and some of the rules for foreigners to stay in the United States. The information is accurate to the best of our knowledge. However, there is considerable complexity as there are several types of visas; it can be applied for in your own country, the rules vary according to your nationality and the regulations.

Please note: OFC Management is not able to contact any Embassies or government institutions in support of an individual attempting to gain entry into a country to attend OFC, including requests for assistance for visas and passports.