This chapter discusses the bureaucratic politics behind the rise of Chinese antitrust regulation. Chinese antitrust agencies are seldom subject to judicial scrutiny, and as a result, have monopolized the administrative enforcement of the Anti-Monopoly Law (AML). The severe sanctions that can be imposed under the AML give high-powered incentives to both government enforcers who want to expand their policy control and businesses who wish to use the law strategically to sabotage rivals. Moreover, the three former Chinese antitrust agencies were not assembled from scratch but were pre-existing departments within large central ministries. Naturally, the bureaucratic mission, culture, and structure of each of these agencies had shaped their enforcement agendas. Much of the discussion revolves around the National Development and Reform Commission (NDRC), as the agency stood out as the most aggressive institution among the three former agencies. Its rich record of enforcement also allows one to assess the link between these institutional factors and the pattern of enforcement. In 2018, the three agencies were merged into a single bureau under a newly created central ministry. The chapter then elaborates on the continuing challenges faced by this new agency, including the bureaucratic hierarchy, the power fragmentation, and the regional inertia.