![The Department of Homeland Security’s Trusted Traveler programs](/uploads/4/9/8/0/49807281/3378437_orig.jpg)
The four Trusted Traveler programs are all based on a common system called the “Known Traveler Number.” When you apply for one of the four programs, the Department of Homeland Security will run a background check to ensure that you are a low-risk traveler. You are then issued a Known Traveler Number that you must enter when booking air tickets or other travel arrangements. You may also be issued a card or passport sticker, depending on which program you choose. Your Known Traveler Number, as well as your membership in the Trusted Traveler program, will be good for 5 years, after which you will need to re-enroll.
All of the programs require you to pre-enroll online, and then visit an enrollment center for a brief interview to have your ID checked and your fingerprints taken.