A Grid for Particle Physics - from testbed to produ ction

The GridPP project, in close association with the European DataGrid (EDG) and the LHC Computing Grid (LCG) projects, reached a key milestone this year with t he successful deployment of a production Grid testbed. This paper describes the valueadded middleware developed to make the testbed function for users across the globe, provides some examples of the use applications have made of it and shares many of the lessons learned. The final section briefly reviews the GridPP approach for movi ng from a testbed-oriented project to a production service able to meet the needs of the Large Hadron Collider (LHC) and other particle physics programmes.