Who is the most influential in Japan's policymaking process? How does the most powerful actor exert influence? What kind of role does a particular political actor play in the process? Although it has been said that bureaucrats rule Japan, I would like to argue that the ruling party is the dominant political actor in policymaking process. And the book's main goal is to elaborate what kind of political power structure the ruling party has developed, and to demonstrate how the ruling party overrules policy preferences of other political actors, such as interest groups, opposition parties, and sometimes even the prime minister, in small business policymaking process.