The country you are going to also matters.

In the UK, for example, many banks do not charge fees to use their ATM and the ATM's clearly state that. Using ATM's attached to banks means avoiding any such fees.

In some countries, there are great rates at exchange houses. That is often the case in eastern Europe, but almost never the case in any country that uses the euro. In the country I work in, I can generally convert dollars or euros to local currency at an exchange loss of less than one percent against the mid-market interbank rate. Sometimes, I can even to three currency transactions, dollars to local currency to a third currency for less than a one percent total exchange loss. In a euro-using country, your exchange loss at an exchange house is likely to be at least 6 - 10%.

Another thing to remember is that it is usually not essential to have local currency when you get off the plane. I cannot think of a major city in Europe that I cannot get into the city center with a credit card. That is where I generally change money, as there are few airports where you get good rates (Zurich, Mexico City, and Chisinau are the only three that come to mind) at exchange houses. If you feel you need a little local money in your pocket, go to McDonalds or a news stand at the airport and make a purchase, Most of them take dollars at an okay but not great rate but with no commission. Give them a 20 and you will get your change in local currency. Heck, even away from the airports, some McDonalds will do that. I remember in the pre-euro days, the best place to change money in Luxembourg was McDonalds. Go there first thing in the morning and get a Big Breakfast and depending on how much local money you needed, give them a US 20 or 50 or 100 and get your change in Luxembourg francs at a better rate than the banks and with no commission (unlike the banks). Or go later and buy a small coke and do the same thing.