If you’ve ever had that moment of panic when you’re ready to leave for the airport, and suddenly can’t find your I.D., then you know the hopeless feeling of mentally watching your fun (or necessary, if it’s for work) trip go right down the drain.

So, what should you do when it happens to you?

First of all, it’s important to find and pack any other documents you have that can identify you or help your case (assuming you don’t have a passport or Global Entry card) – a Social Security card, birth certificate, bank card, insurance card, even utility bills – because you’ll likely have to explain your case to (a hopefully sympathetic) security officer.

If they approve what you’ve brought, you’ll be able to proceed through security with a boarding pass that proves you’ve shown some form of ID.

If they don’t, fear not – you can still complete the TSA’s “identity verification” process, which will include “collecting information such as your name, current address, and other personal information to confirm your identity.”

It will take up to an additional two hours, however, so make sure you arrive at the airport with plenty of time to spare.

Also, it can be a pretty intense process. From one redditor who went through it:

“I give him my name, date of birth, and SSN. He tells me he’s going to relay some questions to me, then proceeds to ask some general questions (credit report-type stuff) then some non-general questions (what cities my parents were born in). After I answered all the questions they gave me the enhanced pat-down and then sent me to my flight.”

If you’ve got copies of your id, you’ll want to bring those, just in case.

Also, with the advent of READ-ID, all of this advice might soon be obsolete. So there’s that.