Regulatory Reform in Japan was among the first in a series of in-depth country reviews on regulatory reform. Since 1999, when the review was published, the Japanese government has introduced a number of measures to enhance regulatory quality and to promote regulatory reform, competition policy and market openness. This publication assesses the progress made, identifies some of the lessons that can be learned about the implementation process and indicates what more can be done in light of current challenges. The monitoring exercise covers the core issues of capacity for regulatory quality, competition and market openness. This study updates information about competition policy in Japan, and such trade-related matters as internationally harmonised measures and conformity assessment processes. It calls attention to the linkages between regulatory policies and tools, and the application of competition and market-openness principles. Innovative efforts, such as the Special Zones initiative, also receive attention. The overall concern is how further progress on regulatory reform can enhance Japan’s growth potential. The report brings out many of the lessons of implementation, which take account of the specificities of the Japanese context, but can be of wider value in other countries as well. What began in the 1990s as an effort to remove regulatory barriers is gaining momentum. Regulatory reform is a dynamic process aimed at improving regulatory tools and institutions, reassessing existing regulations in light of current economic and social developments, and assessing the impact of new regulations while they are in preparation. These tasks call for a whole-of-government approach, which is one of the main challenges for Japan’s next three-year Programme for Regulatory Reform.