A detailed overview of the Illinois basin is followed by less detailed reviews of six other selected interior cratonic basins: the Williston, Michigan, Baltic, Paris, Parana, and Carpentaria basins. The goal is to develop a better understanding of the basin-forming, basin-filling, and basin-modifying processes that control hydrocarbon plays and resultant oil and gas fields in this class of basins. The idea is to describe and document the variations, opportunities, and exploration problems that can be expected.