ONEOK is a company that engages in the gathering, processing, storage, and transportation of natural gas. It operates through the Natural Gas Gathering and Processing, the Natural Gas Liquids, and the Natural Gas Pipelines segments. The company gathers, treats, fractionates, stores, and transports natural gas liquids (NGL), as well as owns natural gas liquids gathering and distribution pipelines, natural gas liquids distribution and refined petroleum products pipelines, and terminal and storage facilities; and operates interstate and intrastate regulated natural gas transmission pipelines and natural gas storage facilities, as well as stores, markets, and distributes NGL products to petrochemical manufacturers, heating fuel users, ethanol producers, refineries, exporters, and propane distributors.