  Results on hard diffraction from CDF are reviewed with emphasis on the
determination of the diffractive structure function of the (anti)proton from
single diffractive and double Pomeron exchange dijet production. Comparison of
the diffractive dijet results with predictions based on diffractive deep
inelastic scattering at HERA shows a breakdown of conventional QCD
factorization. A similar breakdown is observed within the CDF results in
comparing the structure functions obtained from single diffraction and double
Pomeron exchange.
