There's a good blog post by security expert Ross Anderson on how to get money back from the bank for a fraudulent credit card transaction, which may help consumers who've fallen victim to card fraud.
He recounts what happened when a dodgy debit appeared on a credit card his wife uses, and the long rigmarole he had to go through with NatWest in order to get a refund.
He finally had to start a claim against the bank in Small Claims Court before they would refund him, and says:
"So it seems that the optimal bank complaint procedure is one letter, then a writ. But do take care that your case remains on the small claims track."
(Because if the claim gets moved from small claims and you lose, you may be landed with having to pay the bank's legal costs of defending the claim.)
He's helpfully put the documents online.
I've had a couple issues myself over the years but my credit card company (not NatWest) have never quibbled about sorting it out and have in fact been very helpful, fingers crossed that it won't happen again.