International Attendees


Global Access to Hydrometallurgy


Hydrometallurgy welcomes conference attendees from around the world. If you plan to attend the Hydrometallurgy Conference from outside the United States, a U.S. visa may be required. For the best conference travel experience, begin your preparations early.


The following important information will help you successfully navigate the visa application process. Please refer to the U.S. State Department website for more details.


Plan Ahead

You can check the estimated wait time for U.S. visa appointments in your country at the local U.S. Embassy and Consulate’s website. Please contact your nearest consulate as soon as possible to request an interview date. Expect extended wait times exceeding 5 months.


Registration and Letter of Invitation

You must first register to attend Hydrometallurgy before a letter of invitation request can be issued to support your visa application. SME will send a Letter of Invitation to paid registrants upon request. Requests for Letters of Invitation must include your name, job title, company name, mailing address (PO boxes are not acceptable), city, state/province, country, zip/postal code, phone, fax number, date of birth and passport number; as well as the beginning and end dates of travel. Please provide the address, phone and fax number of your local U.S. embassy. All items must be submitted to receive a Letter of Invitation. Note: Invitations are intended to help international delegates raise travel funds or obtain a visa. It is not a commitment from the conference or the organizers to provide any financial support.

Or send to: SME Meetings Dept. 12999 E. Adam Aircraft Circle, Englewood, CO 80112 USA. Obtain a Visa or ESTA Determine if you need a visa or if you are eligible for the Visa Waiver Program (VWP). Attendees needing a Visa: If you need a visa to attend Hydrometallurgy, be sure to apply for the right kind of visitor visa. This is typically a B1 visa to “Attend a scientific, educational, professional, or business convention or conference for a business visit.” You will need: a current machine-readable passport, an in-person interview with the U.S. State Department consulate or embassy in the country where you live, and a letter of invitation from SME to Hydrometallurgy.

You will need:

  • A current machine-readable passport
  • An in-person interview with the U.S. State Department consulate or embassy in the country where you live
  • A letter of invitation from SME to Hydrometallurgy


Attendees Utilizing ESTA

You may travel to the U.S. for 90 days or less without obtaining a U.S. visa, if you’re a citizen of one of the 38 countries participating in the Visa Waiver Program. You must have valid Electronic System for Travel Authorization (ESTA) approval before travel. ESTA requires all international travelers to register in an online database and must complete an application on the ESTA website.

Note: SME cannot intervene on your behalf with the Embassy or U.S. Consulate via fax, phone, surface mail, or email. The U.S. State Department provides information on traveling to the United States regarding passports, international travel, and visas.


Interview Tips

Bring all supporting materials related to Hydrometallurgy to your interview, including your Letter of Invitation, hotel and plane reservation confirmations, conference agenda and any other documentation supporting your participation in the event. Tips: Be prepared to demonstrate strong ties to your country. Consular officers review your application and consider proof of business ownership or employment, social and family relationships and other evidence as proof that you will return to your country. Previous travel to the U.S. or other foreign countries demonstrates good faith.


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