Precision Tests of QCD
  The electron-proton collider HERA allows the study of the partonic content of the proton in regions of Q-squared up to 50,000 GeV$^2$ and values of Bjorken-x down to 10^-5. This paper presents recent precision measurements of structure functions and hadronic final state observables which test QCD over this wide region of phase space. 
David Milstead