Starting May 15, when passengers purchase airline tickets, they will be required to provide their name as it appears on the government-issued ID that they plan to use when traveling. This is the first phase of a new TSA program called "Secure Flight."
So.if you plan to present a driver's license , purchase tickets using your name as it appears on your driver's license. If you plan to present a passport, purchase tickets using the name that appears on your passport. (Here is a list of acceptable forms of identification.)
But rest assured, the system will be pretty flexible. For the near future, small differences between ID and reservation information, such as the use of a middle initial instead of a full middle name or no middle name/initial at all, should not cause a problem for the passenger.
Secure Flight is a multi-phase program developed by DHS that matches passenger information against federal government watch lists for domestic and international flights. Before Secure Flight, airlines themselves were responsible for matching passenger information to the federal watch list. As Secure Flight is implemented, TSA will begin to assume responsibility for the security program.
After August 15, domestic airlines will be required to collect (and passengers will be required to provide) date of birth and gender in addition to name (as it appears on the government ID). By providing these pieces of information under the new Secure Flight program, cases of mistaken identity will be virtually eliminated. For passengers who have had problems in the past, this means that you'll be able to print your boarding pass at home before arriving at the airport. It also means that your 6-year-old won't be misidentified as someone on the Selectee or No Fly lists.