Encore Acquisition Company engages in the acquisition, exploration, exploitation, development, and production of oil and natural gas reserves from onshore fields in the United States. It holds interests in properties, and oil and natural gas reserves located in the Cedar Creek Anticline (CCA) in the Williston Basin of Montana and North Dakota; the Permian Basin of west Texas and southeastern New Mexico; the Rockies, which includes non-CCA assets in the Williston, Big Horn, and Powder River Basins of Montana, North Dakota, and Wyoming, as well as in the Paradox Basin of southeastern Utah; and the Mid-Continent area, which includes the Arkoma and Anadarko Basins of Oklahoma, the North Louisiana Salt Basin, and the east Texas Basin. As of December, 31, 2007, the company had proved reserves of 189 million tank barrels of oil and 256 billion cubic feet of natural gas. It sells its products to end users, marketers, refiners, and other purchasers. The company was founded in 1998 and is based in Fort Worth, Texas.