ONEOK Partners, L.P. is engaged in the gathering, processing, storage and transportation of natural gas in the United States. In addition, the Company owns premier natural gas liquids systems, connecting natural gas liquid (NGL) supply in the Mid-Continent and Rocky Mountain regions with key market centers. The Company operates through four business segments: Natural Gas Gathering and Processing segment primarily gathers and processes unprocessed natural gas; Natural Gas Pipelines segment primarily owns and operates regulated interstate and intrastate natural gas transmission pipelines and natural gas storage facilities; Natural Gas Liquids Gathering and Fractionation segment primarily gathers, treats and fractionates NGLs and stores and markets NGL products, and Natural Gas Liquids Pipelines segment primarily owns and operates Federal Energy Regulatory Commission (FERC)-regulated interstate natural gas liquids gathering and distribution pipelines.