Girder integration NSLS-II

National Synchrotron Light Source II (NSLS-II) will be a 3-GeV 792 m circumference third generation synchrotron radiation facility with ultra low emittance and extremely high brightness. There will be a total of 90 multipole storage ring girders supporting the vacuum chambers, multipole magnets and various pieces of ancillary equipment. A major effort is being made to meet the stringent assembly and alignment requirements for the girder assemblies using relatively few and removable positioning fixtures. Girder assembly and alignment will be accomplished in four phases. Each of these phases will be described along with the fixtures required.