A new border control system the United States will start using to screen short-term foreign travelers in January remains relatively unknown less than a month before launch, and people in the airline and tourism industries are worried the lack of awareness will wreak havoc at airports nationwide.

The new Electronic System for Travel Authorization requires travelers from Visa Waiver Countries who wish to stay in the U.S. for 90 days or less to use the Internet to apply for permission to enter the country three days before departure. Travelers with visas are not affected.

Those who come to the airport without ESTA authorization are likely to be forced to reschedule their flights or cancel, which is causing growing concern among airlines and travel agencies.