The U.S. has
recently implemented strict visa policies to increase
security for our citizens and visitors. It will probably take you
longer to get a visa than it used to, and you should apply well in
advance of your departure date. For details that
may apply specifically to your country, see information posted by
your nearest consulate or embassy.
It has come to our attention that some US consulates are requiring a printed invitation on ILCC 2006 letterhead and with an original signature as part of the visa application. The Organizing Committee will provide such letters on request.
of Visa Waiver Countries
WEBSITES - "Information for Foreign Visitors"