U.S. Customs and Border Protection (CBP) announced on April 26, 2013, that it has automated the Form I-94, Arrival/Departure Record. The I-94 provides international visitors evidence that they have been lawfully admitted to the United States, which is necessary to verify registration, immigration status, and employment authorization. Affected visitors will no longer need to fill out a paper form when arriving in the U.S. by air or sea. CBP will now generate records of admission using traveler information already transmitted electronically. The change was implemented at air and sea ports on April 30 at Charlotte-Douglas International Airport, Orlando International Airport, Las Vegas Airport, Chicago O'Hare, Miami International Airport, and Houston Bush Intercontinental Airport. It will be rolled out across the country through May 21. Travelers wanting a hard copy or other evidence of admission may access that information here if they did not receive a hard copy attached to their passport.
From there, individuals can print a copy of the I-94 based on electronically submitted data, including the I-94 number from the form, to provide as necessary to benefit providers or as evidence of lawful admission.
The announcement is available here.