ONEOK, Inc., a diversified energy company, engages in the gathering, processing, storage, and transportation of natural gas and natural gas liquids in the United States. The company operates through three segments: ONEOK Partners, Natural Gas Distribution, and Energy Services. The ONEOK Partners segment is involved in gathering, processing, storing, and transporting natural gas; owns and operates regulated natural gas transmission pipelines, natural gas storage facilities, and natural gas gathering systems for unprocessed natural gas; and owns natural gas liquids systems in the Mid-Continent and Rocky Mountain regions. This segment offers its services to petrochemical manufacturers, heating-fuel users, refineries, and propane distributors. The Natural Gas Distribution segment provides natural gas distribution services to residential, commercial, industrial, and transportation customers, as well as wholesale and public authority customers in Oklahoma, Kansas, and Texas. The Energy Services segment offers nonuniform natural gas supply and risk-management services for natural gas and electric utilities, and commercial and industrial customers through its network of leased storage and transportation capacity. ONEOK, Inc. was founded in 1906 and is headquartered in Tulsa, Oklahoma.