This is maybe the most reliable way of getting at your cash from abroad but you might lose up to 3-5% on each withdrawal.
You will also be limited to how much you can withdraw in any 24 hours period however so it’s not so useful if you plan on, say, buying a car with your money.
In some countries it can also be murderous to find an ATM machine in the third world. There might be only one machine in the entire town that accepts foreign cards and it may well be out of order. This is getting easier and easier though and you can still walk into major banks and have cash advanced with the help of a clerk.
Remember that ATM’s are basically computers in a wall. And like any computer, they just love fucking you up. You may well have plenty of cash in your account but some glitch on the line convinces the computer you’re a scammer and it denies you any cash.
It may even swallow your card if it gets really pissed. Then you have to turn up at the bank the next morning and explain in the local language to a group of distrustful bankers what happened. Good luck with that. In the meantime you’re left broke and can’t even prove that you’re remotely solvent when you try to get credit at the local bar.
In dangerous countries be careful around ATM machines and only go to them during the day. Muggers may well wait to see who’s leaving the cash machines. Put all your cash away before you leave and keep your eyes open.