What are the advantages of possessing an IDL? Usually, local traffic police officers of another country would not be able to understand the language on your native driver's license. They would, however, be familiar with at least one of the 8 languages on an IDL. Travel officials, in Europe, say that the IDL is advised for most countries. In over 40 countries worldwide, you are unable to rent a car unless you possess an IDL. While an IDL is not a requirement for driving in some countries, it is still an advantage for a motorist.