This article describes and analyses the evolving regulatory game in the post-privatized water industry. It highlights a regulatory environment that is more complex than that which existed under public ownership, and an industry which is subject to heavier regulation in the private sector than it was in the public sector. There has been erosion of the strict public/private divide following privatization. The article highlights an episodic and seemingly incongruous policy-making environment that defies consistent characterization: sometimes private consensus is the main feature and sometimes it is public conflict. It also illustrates that while there are two broad-based constituencies of interest active in the water sector - cost and environmental - the composition of these coalitions mutates depending on the issue being considered. Indeed, there are occasions when core constituency participants 'defect' and join the 'opposing side'.