Public and private sector actors increasingly recognize the need for action to address climate change. With the introduction of “carbon sinks” into the policy dialogue, the notion of managing human activities to mitigate climate change has extended beyond energy systems and emissions of carbon dioxide to include management of the carbon cycle itself, through manipulation of the terrestrial and oceanic realms. The number of decision makers involved and scope of managing the carbon cycle deliberately for climate purposes raises enormous challenges to governance including identifying appropriate mechanisms where they do not yet exist and adding additional criteria onto existing mechanisms that are already affecting the carbon cycle. In this paper, I define effective carbon governance as limiting the amount of carbon dioxide in the atmosphere. This paper outlines a number of challenges to effective carbon governance at multiple scales using the example of land use in the United States and elsewhere.