Following enactment of the Local Autonomy Law (Chiho Jichi-ho) in 1947, and numerous systemic reforms in the intervening period, in 2000 local government in Japan underwent an overhaul—Heisei decentralization (bunken kaikaku)--deemed on a par with the Meiji Restoration and post-war reforms. Since then there have been further calls for root-and-branch reform of local government, via the introduction of a more decentralized doshusei (state and circuit) system, or regional sovereignty reform (chiiki shuken kaikaku). This resource collates in a single location four valuable types of material compiled and published by The Japan Research Institute for Local Government think-tank, a Public Interest Incorporated Association (koeki zaidan hojin) established in 1974 and now the main center for research on Japanese local government, painting a comprehensive picture of the path trodden by the Institute, and what it has achieved, over the past four decades.