Call your bank or check out its Web page before you leave to try to find out whether a country block is in place at your destination.
Take more than a debit card. "We recommend travelers always carry a mix of payment options that may include credit cards, debit cards, traveler's checks and currency to help them navigate through any circumstance," said Lisa Westermann, assistant vice president of public relations for Wells Fargo Card Services.
If you can't withdraw cash from an ATM, go to a bank. Many U.S. debit cards come with a credit function that allows customers to get a cash advance. The fees and interest are higher than for a debit transaction, but the desperate can't be picky. And if you have your checkbook, American Express offices usually will cash checks for any cardholder.
Make sure you know how to contact your bank from abroad if you need to report fraud or a card malfunction. Your bank can also direct you to a nearby financial institution, and it will sometimes issue you a new card that will work (although it will send the card to your home address; you'll need to have someone forward it to you).