James van Dyne explains how driving licences work in Japan:
There’s 3 different levels of license in Japan, green, blue, and gold. You get a gold license by renewing twice without (any?) infractions or accidents. Having a gold license will also entail you to a 10% discount on your auto-insurance. But if you get tickets with a gold license, they’ll move you down to blue on your next renewal. Even though I’ve been driving for over 15 years, my driving history in Japan is only 3 years, so I was on a green and am now blue.James Van Dyne
That’s a neat system. We have a similar way of doing things in the UK. Infractions of the Highway Code will get you ‘points’ on your licence, which in turn result in higher insurance premiums. Minor infractions might get you three points, more severe ones up to twelve points and they take away your licence if you get twelve points in a three year period.
It’s nice that you are rewarded for good driving in Japan.
He explains a bit more about the process in his post, which appears to be as well organised as you would expect.