The downstream gas industry includes the processing of gas, the transportation of gas though the national transmission system (NTS) and local gas distribution networks (GDNs) (gas transportation), arranging for gas to be carried in the NTS and GDNs (gas shipping), and the supply of gas to end consumers (gas supply). These activities are regulated by Ofgem. The downstream industry can also include buying and selling gas in the gas wholesale market (gas trading). See also midstream (gas) and upstream (gas). For more information, see Practice note: Downstream gas industry: overview.