Now that Japan has accepted the comply-or-explain principle, the fact that the EU also adopted that principle in 2006, and the manner in which it was done, is quite relevant:
http://bdti.mastertree.jp/f/jo9kqg7u
The Board Director Training Institute (BDTI) is a "public interest" nonprofit in Japan dedicated to training about directorship, corporate governance, and related management techniques. It is certified by the Japanese government to conduct these activities as a regulated nonprofit. Read a summary about BDTI here, and see a menu of its services for both corporations and investors here.