Tenet Healthcare Corporation, an investor-owned health care services company, owns and operates acute care hospitals, ambulatory surgery centers, diagnostic imaging centers, and related health care facilities in the United States. The company’s general hospitals offer acute care services, operating and recovery rooms, radiology services, respiratory therapy services, clinical laboratories, and pharmacies. It also provides intensive care, critical care and/or coronary care units, physical therapy; and orthopedic, oncology, and outpatient services; tertiary care services, such as open-heart surgery, neonatal intensive care, and neuroscience; quaternary care in areas, including heart, liver, kidney, and bone marrow transplants, as well as burn services; gamma-knife brain surgery; and cyberknife radiation therapy for tumors and lesions in the brain, lung, neck, and spine. The company also owns an interest in a health maintenance organization and operate various related health care facilities, which include a long-term acute care hospital and various medical office buildings; revenue cycle management and patient communications services businesses; physician practices; captive insurance companies; management services business that provides network development, utilization management, claims processing, and contract negotiation services to physician organizations and hospitals that assume managed care risk; and occupational and rural health care clinics. As of December 31, 2011, it operated 50 hospitals, including 4 academic medical centers and 1 critical access hospital, with a combined total of 13,453 licensed beds primarily serving urban and suburban communities in 11 states of the United States; and 98 diagnostic imaging centers, ambulatory surgery centers, and urgent care centers, as well as 1 emergency department in 12 states of the United States. Tenet Healthcare Corporation was founded in 1967 and is headquartered in Dallas, Texas.