As of Jan 12th 2009, visitors to the US must register with the Electronic System for Travel Authorization (ESTA).

The Department of Homeland Security is introducing the new system to replace the current Visa Waiver Program (VWP). All countries currently eligible to use the VWP will be legally required to obtain authorization before their departure. Applications are free of charge and are processed in about four seconds.

Approximately 14,000 people are currently registering with ESTA daily with an approval rating of 99.6%. Travelers should be aware that a number of websites that are not endorsed by the US government are charging a fee for ESTA information or application processing.