You do not need to have an airline or hotel reservation booked to apply for a Travel Authorization. If you are planning a trip to the United States within the next 6 months you are recommend to apply already now. If you travel to the United States and are denied entry, you will never be able to enter the United States on the Visa Waiver Program again.

• If denied, you will have time to apply for U.S. visitor visa which can take several weeks or months depending on how busy the U.S. embassy or consulate is
  
  
• An approved Travel Authorization means that your passport details has been cross checked against a number of U.S. official databases but without any findings
  
  
• The Travel Authorization is valid for two years (unless your e-passport expires earlier) and can easily be updated for future visits
  
  
• Travel to the U.S. on short notice

• Any traveler who wish to visit the United States under the Visa Waiver Program via air or sea
  
  
• Any Visa Waiver traveler who transits through the United States under the Visa Waiver Program
  
  
• Any traveler also includes children and infants visiting/transiting on the Visa Waiver Program

• After January 12, 2009 all travelers must be approved to travel to the United States via air or vessel
  
  
• Travelers transiting through the United States under the Visa Waiver Program must also possess an approved Travel Authorization after January 12, 2009
  
  
• If your application for a Travel Authorization is denied, you must apply for a B-1 Visitor Visa or B-2 Tourist Visa which can take weeks or months to obtain