  We describe the particle identification capability of the CLEO RICH system.
This system consists of a 1 cm thick LiF radiator coupled to a photon detector
that uses wire proportional chambers filled with a mixture of CH$_4$ and TEA.
We discuss the yield of photoelectrons observed per ring and the angular
resolution. We show the efficiencies achieved for particle identification and
the associated fake rates from data collected with both CLEO III and CLEO-c
detectors. Finally we show examples of the particle separation ability which is
excellent for both CLEO III and CLEO-c data.
