  Instantons create a non-local interaction between the quarks, which at finite
baryon density leads to the formation of a scalar diquark condensate and color
superconductivity. A mean field approach leads to a self-consistent description
of the $<\bar q q>$ and $<q q>$ condensates and shows the inevitability of a
BCS type instability at the Fermi surface. The role of the rearrangement of the
instanton ensemble for the QCD phase transitions is also discussed.
