It's almost impossible to travel without a credit card, but attempts to thwart increasingly clever fraud artists are making it annoying to travel with one.

Like the fishermen who trap dolphins while trawling for tuna, the banks' extensive anti-fraud nets are a hassle to business travellers whose work takes them to known fraud centres, such as Eastern Europe and parts of Africa, or whose spending and travel habits are irregular.

Case in point: Michael Bociurkiw's recent trip to Lesotho on contract business for the United Nations. Two weeks ago, at check-in, Bociurkiw's credit card was declined, blocked by his bank's anti-fraud software. Embarrassed, he paid cash. He knew from experience to carry a backup card in a backup wallet.

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When he used it that night to pay for dinner, he was declined a second time. That was a first. Multiple attempts at collect and Skype calls later, his cards were finally unblocked.

According to the Canadian Bankers Association, in 2009 more than $350-million in cash and goods was taken from Canadian card-holders, almost half of that using counterfeit cards. Banks are understandably concerned, and have massive computer systems devoted to preventing fraud. Rick Rennie, MasterCard Canada's vice-president of customer security, says that computers "compare legitimate transactions against known fraud patterns, and look for variances from the card-holders' normal spending patterns."

Sometimes, innocent travellers are caught in the net. But if you know the tricks, you can minimize the chance of getting tripped up or, if you do get blocked, get back on track before your itinerary gets derailed.

Here's some advice to keep you flush on the road:

CARRY BACKUP CARDS

And make sure they're from different banks. Bociurkiw carries three cards in three different wallets, just in case. He also carries a backup bank card (a debit card from Swiss issuer UBS) in case his own bank card gets cancelled by fraud flags.

CALL YOUR ISSUER BEFORE EACH TRIP

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This is the surest (but by no means certain) way of avoiding on-the-road hassles. Rennie says some of the blocks are imposed automatically, with no human participation.

GIVE YOUR BANK CONTACT INFORMATION

Though this is not fail-safe, Rennie says some Canadian issuers are looking into systems to let customers know their account is about to be flagged, giving them the chance to text back if the charges are customer-approved.

AVOID SMALL AIRPORT TRANSACTIONS

Speaking from bitter personal experience, Bociurkiw says, "If you've been overseas for a while and you're back in North America and you use [your card]for a phone call or a luggage cart, it automatically flags your card." Cory Siddens, a fraud expert at CyberSource, says the small-charge check is a common fraud technique, as people who have stolen or phished an account number buy "something that costs a dollar or something that isn't stolen very often" before going on to a more substantial charge.

TRACK YOUR TRANSACTIONS

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If you don't remember your last 10 charges, or don't have the receipts in front of you, getting your card unblocked can be more complicated.

Special to The Globe and Mail

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