This paper examines how changes in governmental and social influences affect environmental enforcement in Guangzhou city, China, between 2000 and 2006. The paper finds that a form of “decentered regulation” has developed. Regulatory enforcement is no longer the sole affair of the government and the regulatory bureaucracy, but has been increasingly influenced by societal forces. The transformation over time shows the promises and limits of decentered regulation in Guangzhou's dynamic authoritarian setting. Analyzing a set of longitudinal survey data and qualitative interviews, the paper finds that by 2006, the rise of civil society and its increased support for protecting the environment had a double-edged impact on the enforcement of environmental regulations. The paper demonstrates that on the one hand, by 2006, when government support for enforcement was low, societal forces developed an ability to counterbalance such lack of governmental support and positively influence enforcement. However, it also shows that when government support was high, a concurrent rise in societal support created a negative effect on enforcement. Thus too much societal support can become an enforcement burden.