Make copies of the front and back of each card that you plan to bring. You want to make sure the account number and the toll-free customer service number are legible. If you're traveling outside the U.S., check to see if the number you can call to reach customer service from outside of the country is on the back. If not, call your issuer and ask for it. You'll want two copies; one to leave with a trusted friend or family member back home, and one to bring with you.
Adam Levin, chairman and co-founder of Identity Theft 911, suggests bringing digital "copies" if you're tech-savvy. "I would have a copy of my critical documents that would identify me if money is being wired to me. I would scan in my credit cards, my passport and driver's license. I would scan that into my computer and save it on an encrypted thumb drive," he says.
As with paper copies, store these in a safe place, but not in the same place as your actual cards. Levin suggests wearing the thumb drive on a lanyard around your neck, tucked under your shirt.