If you plan to attend the ATS 2025 International Conference and will be traveling to San Francisco, CA from countries other than the United States, please be aware of the U.S. passport and visa policies for citizens and visitors.

What is a U.S. Visa?

A citizen of a foreign country who seeks to enter the United States generally must first obtain a U.S. visa. Visas are 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.

U.S. Visa Waiver Program (VWP)

The Visa Waiver Program (VWP), administered by the Department of Homeland Security (DHS) in consultation with the State Department, permits citizens of 41 countries to travel to the United States for business or tourism for stays of up to 90 days without a visa. In return, those 41 countries must permit U.S. citizens and nationals to travel to their countries for a similar length of time without a visa for business or tourism purposes. Since its inception in 1986, the VWP has evolved into a comprehensive security partnership with many of America’s closest allies. The VWP utilizes a risk-based, multi-layered approach to detect and prevent terrorists, serious criminals, and other mala fide actors from traveling to the United States. This approach incorporates regular, national-level risk assessments concerning the impact of each program country’s participation in the VWP on U.S. national security and law enforcement interests. It also includes comprehensive vetting of individual VWP travelers prior to their departure for the United States, upon arrival at U.S. ports of entry, and during any subsequent air travel within the United States.

• Visa Waiver Program Requirements
• Visa Waiver Program Countries
  Note: The citizens of the new countries of Curacao, Bonaire, St Eustatius, Saba and St Maarten (the former Netherlands Antilles) are not eligible to travel to the United States under the Visa Waiver Program if they are applying for admission with passports from these countries.
• Electronic System for Travel Authorization (ESTA)

If you are not a citizen of these countries or are not eligible to participate in the VWP, please click here, to find out how to obtain a visa. If you do not have access to the Internet, contact your nearest U.S. Embassy or Consulate for further information.

You should be prepared to provide supplementary information explaining the purpose of your travel with your visa application. In this regard, the following supplementary information is recommended:

• A letter of invitation to ATS 2025. You may generate a customized letter here or request that one be mailed to you by e-mailing your name, address, passport number, and arrival and departure dates to membership@thoracic.org. Please be sure the letter of invitation is issued to the name as it appears on your passport and not the name that is in your ATS membership profile.
• If you are a speaker or have an accepted abstract to ATS 2025, please include your acceptance letter with your supplementary information.
• Please provide a letter from your institution, training director or employer stating that you have been given time to attend ATS 2025 and are expected back at your place of employment on a specific date. Be sure the letter uses the name that is on your passport.
• Provide information on your ATS 2025 registration (confirmation number), hotel confirmation and flight information. Be sure you register with your passport name and that your hotel and airline reservations are also made in the name on your passport.

This supplementary information will demonstrate to the consular officer reviewing your visa application that you are sincere about attending ATS 2025, to garner both personal and professional benefits from the conference events and sessions, and then return to your country to share this informational gain with your professional colleagues. It is crucial that the name on all documentation in your visa application file matches the name on your passport.

Having a U.S. visa allows you to travel to a port-of-entry, such as an airport, but does not guarantee entry into the United Staes. Once you arrive in the U.S., you will need to pass through Customs and Border Protection control for final approval to enter the country.