The injection operator for a carbon dioxide sequestration project must control the reservoir and associated pore space within the project boundaries to allow for orderly development of the storage facility. A large number of interest owners within a project area is likely to make reaching unanimous agreement among all owners of pore space unlikely, and thus control of the reservoir difficult. In order to facilitate geologic sequestration of carbon dioxide on privately owned land in the United States, or on land for which the minerals or pore space are privately owned, a scheme for aggregating the ownership of pore space is needed. To allow geologic sequestration projects to move forward with less than unanimous consent of interest owners, states can employ various methods of aggregating pore space ownership. This paper examines oil and gas unitization statues and statutes creating groundwater districts to find legislative regimes useful for achieving pore space ownership aggregation. Among the approaches discussed, aggregation of pore space ownership through a unitization model is the most likely choice. Taking that one step further and setting up new unit operating agreements for enhanced oil recovery to serve as a repository for incremental geologic sequestration, and eventual full sequestration activities, provides a firm path toward reducing carbon dioxide emissions while respecting property rights. This paper also compares the few existing pore space aggregation statutes in the United States, which achieve aggregation of pore space ownership through either unitization or eminent domain. The state that appears to be the best equipped to deal with aggregation of pore space ownership is Wyoming. Wyoming has been a leader in developing legislation to deal with pore space ownership before other states. North Dakota and Utah are also very well situated to move forward with carbon sequestration activities. / text