Overview of the 63000 PWO Barrel Crystals for CMS_ECAL Production

In March 2007, the PWO crystal production for the barrel part of the CMS electromagnetic calorimeter has been completed. Since September 1998, 63000 crystals (61000 in Russia, 2000 in China) have been produced, received and tested in two regional centers (CERN and INFN Rome). This paper presents an overview of the procedures used from the R&D phase up to the final large scale reception and quality control. The crystals characteristics and the lessons learned from the production of this unprecedented amount of crystals in a HEP experiment are also presented.