Invitation Letters from the National Space Society
You may need an official invitation letter before applying for a visa to attend the International Space Development Conference (ISDC). Visitors from outside the United States are required to obtain this letter from the National Space Society (NSS) if a visa is needed for entry.
An invitation letter confirms your participation in the ISDC and can be included in your visa application at your local U.S. embassy or consulate. We recommend applying for your visa as soon as possible, as processing times can sometimes take longer than expected.
If you are attending in connection with an NSS space contest, such as the Gerard K. O’Neill Space Settlement Contest or the Live in a Healthy Space Design Competition, please click here to request your invitation letter.
For all other ISDC attendees, please click here to request a general invitation letter.
NEW - Invitation Letters for Next Year's ISDC:
Invitation letter requests are now available for ISDC 2027 in Los Angeles, California.
For NSS space contest attendees, please click here to request your invitation letter.
For all other ISDC attendees, please click here to request a general invitation letter.