Results on soft and hard diffraction obtained by the CDF Collaboration at the Fermilab Tevatron {bar p}p Collider are reviewed with emphasis on aspects of the data that point to the underlying QCD mechanism for diffraction. The results are interpreted in terms of a phenomenological approach in which diffraction is due to an exchange of low-x partons subject to color constraints.

Experimental results on hard diffraction from CDF and D0 at the Tevatron are reviewed and compared with results from H1 and ZEUS at HERA and with theoretical expectations.

We present new results from studies on diffractive dijet production and exclusive production of dijet and diphoton obtained by the CDF Collaboration in proton-antiproton collisions at the Fermilab Tevatron.

Results on diffractive particle interactions from the Fermilab Tevatron {bar p}p collider are placed in perspective through a QCD inspired phenomenological approach, which exploits scaling and factorization properties observed in data. The results discussed are those obtained by the CDF Collaboration from a comprehensive set of single, double, and multigap soft and hard diffraction processes studied during the twenty year period since 1985, when the CDF diffractive program was proposed and the first Blois Workshop was held.

The diffractive program of the CDF Collaboration at the Fermilab Tevatron p{bar p} Collider is reviewed with emphasis on recent results from Run II at {radical}s = 1.96 TeV. Updated results on the x{sub B{sub j}} and Q{sup 2} dependence of the diffractive structure function obtained from dijet production, and on the slope parameter of the t-distribution of diffractive events as a function of Q{sup 2} in the range 1 GeV{sup 2}