GridPP is a collaboration of particle physicists and computer scientists from the United Kingdom and CERN. They manage and maintain a distributed computing grid across the UK with the primary aim of providing resources to particle physicists working on the Large Hadron Collider (LHC) experiments at CERN. They are funded by the UK's Science and Technology Facilities Council. The collaboration oversees a major computing facility called the Tier1 at the Rutherford Appleton Laboratory (RAL) along with the four Tier 2 organisations of , , and (formerly LT2). The Tier 2s are geographically distributed and are composed of computing clusters at multiple institutes.