Here are a couple of choice links I think everyone will enjoy....
Firstly, rental terms from Hertz (just selected it at random)
"At the time of rental the driver must present a
valid national driver's license which has been held for at least
1 year, provided your national driver's license is in Roman script.
All licenses issued in the
European Union are accepted.
All other licenses in Roman Script are accepted for renting, however, an International Driving Permit is highly recommended as you may be required to present it to the authorities.
With all
Non-European Union driver's licenses
not in Roman Script, an International Driving Permit (IDP) is mandatory"
Now here is the official AAA website that says which countries require an IDP....
www.aaa.asn.au
which is hilarious as it says the USA is "recommended" and that every European country I looked up says "Yes"
As many people have posted on this forum, France, Italy, Germany, Switzerland, USA never require an IDP. I have been pulled over by cops in France and the USA and they never asked for an IDP. I have been issued speeding fines in other countries and they didn't ask for an IDP.
So the question is, who or what is the authority as to whether an IDP is required? Not the police or the rental car agencies it seems....