The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built in Oak Ridge, Tennessee funded by the U.S. Department of Energy (DOE) Office of Science. The SNS will provide the most intense pulsed neutron beams in the world for scientific research and industrial development. At a total cost of $1.4 billion, construction which began in 1999 and will be completed in 2006 the culmination of the collaborative efforts of six National Laboratories (Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge). Powerful neutron beams will be produced in the SNS facility by bombarding a mercury target with energetic protons from a large accelerator complex. A UHV environment is needed in the accelerator to minimize beam losses as the beam is accelerated from the ion source, where low energy particles are produced, through a series of accelerating cavities eventually accelerating the beam to 88% the speed of light with a capable of depositing 1.4 MW on the target at a beam energy of 1 GeV. The component parts of the accelerator will be briefly described specifically addressing the design and construction of the numerous vacuum systems that support accelerator operations. In conclusion the current status of the installation and commissioning of the various vacuum systems will be presented.