We will be in Europe for 12 days - 9 will be using Euros and two days in Switzerland. How do we convert US dollars to local currency? And if we use a credit card will that work best? Once we leave Italy and go in to Switzerland how do we cash out what Euros we have before having to convert over to Swiss money?
Use your atm card in a machine. Best rate. Open an account at a credit union that does not charge 3% foreign currency fees. I always hang on to my extra euros for my next trip. You'll get majorly dinged by fees if you try to do a cash-for-cash exchange.
I agree with using ATMs for your cash. Only take out what you think you will need, and at the end of your Italy stay, just use the rest of your euro cash for your hotel bill. (I also bring home "leftover" euro for the next trip.) Then just get more once you enter Switzerland.
Don't exchange cash for cash - use your ATM or debit card as others have said, for an electronic conversion. If you want to take some local currency with you (I like to do this), buy 50 or 100 euros from your bank. But get the bulk of your cash from ATMs. Many credit cards have a fee for foreign transactions. If you have a Capital One card, it has no foreign transaction fees. Call your credit card company and ask what their fee is, so you won't be surprised when you get the bill. Also tell them which countries you'll be in and when, so they won't flag your account. Europe is more of a cash society than the U.S. I bring my credit cards for hotel charges or other big purchases (I'm a sucker for museum catalogs). Otherwise, for food, tickets, transit, etc. I use cash. And I also recommend saving your euros for the next trip.
On one trip to Europe I was in Switzerland for two days before I found out they don't use the euro (a Swiss friend clued me in at a restaurant)! If you want to unload euro without exchanging them, you can pay for things at the airport with euro, the vendor will do the conversion for you and give you back change in Swiss francs; this may work in other places as well, it did for me, but that was a long time ago. Or, on your last stop in Italy, pay with euros for as much as you can, then put the balance on a credit card.
Agree with everyone...ATM is best for getting cash no matter where you're traveling. If Switzerland is your last stop, then just try to manage your Euro so that you don't leave Italy with a bunch of cash. A few years back, I went to Lausanne from Italy and simply used an automated machine at the train station in Lausanne to convert whatever small amount of Euro I had left to Swiss Francs for a fee (needed money for a taxi...used a bank ATM later that evening). It looked similar to an ATM machine...perhaps that route will work for you. If not, there's always the exchange desk (again for a fee) or just take a bit home. I always end up with some small amount of foreign currency around the house.
JR, As mentioned, the best way to obtain local currency is from an ATM, as that provides very good exchange rates. However, a couple of points to keep in mind. Your travel funds must usually be in a chequing account with a four number PIN. Also, it's a really good idea to take a "backup" ATM card, in case there are any problems with your primary card (I've had that happen). It's also a good idea to take at least one credit card. Visa and MasterCard are more widely accepted than other cards. Note that many smaller shops, etc. in Italy accept only cash. I'd suggest getting a small quantity of Euros (€50-100) from your local Bank to provide expense money until you get settled in your first location (ie: Cabs, meals, Coffee or whatever). ONE VERY IMPORTANT POINT - BE SURE to notify all your financial institutions that you'll be travelling in Europe, so they don't "freeze" your ATM or credit cards when they see transaction activity in Europe. Regarding the issue of "leftover cash", after you've been there for a few days you should be able to get an approximate idea of your daily expenses. Try to ensure that you have just enough on hand for the duration of the trip. If necessary, take out another €20-50 to last until you leave for Switzerland (although you will of course have to pay bank fees for the withdrawal). You likely won't be able to change Euro coins to Francs, so use them for small purchases. You'll probably still have a few left over for "souvenirs". The same method applies when you leave Switzerland. If you're really concerned about getting rid of leftover cash, you could stop at one of the airport currency exchange shops, but they usually have dreadful exchange rates or high fees. Something to use only as a last resort! Cheers!