American Express has a network of overseas offices where no commission is charged for cashing their TC's. They are convenient in better stores and restaurants, and the cash advance privilege can be useful. Each time you exchange money from one currency to another, be it dollars to francs or pounds to marks, you lose money. Try not to cash more money into a particular currency than you think you'll use. The fee for changing money is generally about one percent.
Banks give the best rate of exchange and have lower service charges.
Currency exchange services can also be found in most railway stations and airports but at slightly poorer rates. Generally, hotels and restaurants offer the worst rate of exchange and have high service charges. Some ways of sending emergency funds are faster than others, but give those at home maximum notice before you think you'll run out. If you lose your wallet and you're near a Western Union Office in the United States, you may be able to be rescued on the same day. But if you're abroad, you may have to wait for a week or even two.