Don't think about it!

No, seriously, bear in mind that as soon as you leave main roads, the signs will be in Japanese only. So if neither you or your navigator reads Japanese... good luck!

According to the Japan National Tourist Organisation (see link on left), traffic congestion and parking can also be problems in cities.

Of course Japan is one of the few countries which agrees with the UK about which side of the road to drive on, so that's a plus.

But generally, hiring a car is not recommendable. People who think nothing about hiring cars all over Europe etc. should think twice about considering it in Japan, because of the writing issue. It can be very interesting to see how certain Japanese "Kanji" characters crop up again and again in signs for place-names (the characters for island, river, temple, field etc.) but the difficulty of deciphering words make it tricky to make a quick decision about which turn-off to take at the next junction!

If you are determined to drive, you'll need to have both your normal (national) driving licence AND an International Driving Permit.

People who have rented cars in Japan recommend that you get one with a satellite navigation system fitted (called Car-Navi or -Nabi in Japan), saying that even if you can't get it to talk English, it's extremely helpful.