We experienced two occasions on our recent trip to Ireland where a credit card transaction was run in USD without us being asked whether we wanted the transaction in Euros or USD beforehand. We brought a Capitol One Venture card specifically to avoid the foreign transaction fees, and were more than a bit annoyed, as each time we were told that the transaction could not be voided (which I believe was not true, since I had not signed the slip on any of these purchases). A 3% transaction fee was therefore applied by the "Irish end' of the transaction, and there was nothing we could do. This happened in the bar of the Ashling Hotel in Dublin and at the checkout desk of the Oakwook Arms Hotel in Shannon. Simply put, specify at the very beginning of EVERY credit card transaction that you want the charge to be applied in Euros, at least if you have a no-foreign-transaction fee card.