**IMPORTANT NOTE on the Visa Invitation Letter: Attendees from certain countries are required to obtain a US visa when attending ISPSD2018. Some embassies may need to verify that registration fees have been paid in full and may require applicants to appear in person for an interview, causing delays in the application process. Applicants affected by these procedures are informed that additional screening is needed. Therefore, attendees should apply for a visa no later than three months prior to the conference.

After you complete your online registration, you will receive a confirmation email which will serve as your invitation letter for the visa application purpose. If you need further assistance, please contact the general chair at

US Entry Visa Policies

Citizens of countries other than Canada and those covered by the Visa Waiver Program (listed below) must obtain a Business Visitor Visa (B-1). Information on the B-1 visa can be found here (PDF, 362kB). A passport with a validity date at least six (6) months beyond the applicant's intended period of stay in the United States is required.

Citizens of Canada, holding a valid Canadian passport or Nexus card, are eligible to stay in the United States for 182 days over a 12 month period without a visa.

Citizens or nationals of the following countries* are eligible to travel to the United States for tourism, business, or in transit for up to 90 days without obtaining a visa under the Visa Waiver Program:

*defined as per the Visa Waiver Program

Please note that the above information is provided in good faith as a service to our foreign guests. Be advised that regulations may change and that the only authoritative source of information is the US Government website (linked below). It is the attendee's responsibility to verify this information with official resources.

Please visit travel.state.gov for full details on entry requirements to the USA.