Q. International Driver's License
An international driver’s license or international driver’s permit is a translation of information contained on a person's foreign driver license. People who need to drive in the U.S., but are not legal residents can apply for it before they leave home. To obtain an international driver's license for vacation/holiday visits to the U.S., foreign drivers should contact their own government.
The following fact sheet from USA.gov about foreign visitors driving in the U.S. may be of interest: http://www.usa.gov/Topics/Foreign_Visitors_Driving.shtml
American citizens who intend to drive overseas should check with the embassy or consulate of the countries they will be visiting for information on whether they will need to obtain an international driver’s license or road permit, and what the auto insurance requirements are. If you need an international driver's license, check with the American Automobile Association or other motor club about obtaining an IDL in the U.S. before you leave. Some countries may allow you to use your U.S. license.
The US State Department has a web site which gives information on driving abroad: http://travel.state.gov/travel/tips/safety/safety_1179.html
Please contact the Department of Transportation (DOT) at the state level if you have a specific question concerning the international driver’s license. Links to the state DOT web sites are available on: http://www.fhwa.dot.gov/webstate.htm