The tokamak basic machine of magnets and vessel with its in-vessel components needs a number of services (further details can be found in the linked sections of the ITER Technical Basis):

• cooling water to remove the heat deposited by neutrons, and by radiation, in the materials surrounding the plasma ;
• cryogenic coolant to maintain the magnets at temperatures suitable for superconductivity (~4K) and to maintain cryogenic vacuum pumping panels in the vessel and cryostat;
• radiofrequency waves and high energy particles conducted along waveguides and beam lines through the vessel ports to heat the plasma;
• a fuel cycle system to inject fuel into the plasma by fuel pellets and gas puffing at the edge, to exhaust fuel gases and impurities from the plasma and to collect and process any contaminated leaks throughout the plant, and to process these sources to remove fuel for reinjection and to store impurities for re-use or disposal;
• pulsed electrical power to the magnets and to the power tubes and beamlines of the heating systems;
• remote handling systems to replace in-vessel components and to refurbish them in the hot cell;
• a control system linking diagnostics and equipment to local control/interlock centres and to the central control and data logging system;
• miscellaneous plant systems which provide basic gases (e.g compressed air, nitrogen) and liquids (e.g for fire fighting or sanitation) as well as radiological monitoring and plant sampling systems.