Visa Information

Visa Requirements

All visitors to the United States must have a valid passport whose expiration date is at least six months after the end of your intended travel period. Visitors from non-exempt countries will most likely require a B-1 Business visa. Nationals of several countries who are members of the Visa Waiver Program can travel to the United States for no more than 90 days without a visa. When uncertain as to the requirements for the entry visa to the United States, please contact the United States embassy or a consulate as early as possible. For quick references, please click the links below.

Letters of Invitation

For many people, letters of invitation help smooth the visa process and we wish to support international attendees in their efforts to secure the needed travel documentation. However, in order to receive a letter of invitation, the meeting organizers must be assured that you intend to attend the meeting if your travel request is granted.

Letters of invitation may only be issued to those who meet at least one of the following criteria:

  1. Current members of ISSX;
  2. Individuals who have submitted an abstract to the meeting;
  3. Invited speakers;
  4. Those who have registered and paid to attend the meeting.

If you meet one of the above criteria and would like a letter of invitation, please send your request to ISSX at

The letter of invitation does not financially obligate ISSX in any way. All expenses incurred in relation to the meeting are the sole responsibility of the attendee. Please note that we cannot guarantee that you will ultimately receive a visa. The decision to grant visas is at the sole discretion of the embassy/consulate. The meeting organizers cannot change the decision of the governmental agency should your application be denied. 

Due to the costs involved, ISSX cannot send letters of invitation via express mail services.