  Structure function data together with other measurements from fixed-target
deep inelastic scattering and hadron-hadron collider experiments which
contribute to our knowledge of the parton density functions are reviewed. The
inclusive cross-section measurements of neutral and charged current
interactions at HERA are presented and their impact on the parton density
functions is discussed. Future prospects for an improved knowledge of the
parton density functions at large x are briefly mentioned.

High Energy Physics - Phenomenology