The Constitutional Revision Research Project seeks to follow, analyze, and document constitutional discussion in Japan.

The Constitution of Japan (also known as the Postwar Constitution) went into effect in 1947, replacing the Meiji Constitution of 1890. It is recognized as the oldest unamended constitution in the world as of 2022, having never undergone revision in over 70 years since its promulgation. Throughout this time, constitutional revision has become an important subject of vigorous debate and discussion in Japan and around the world.*