  Charged lepton flavor violation is an unambiguous signature for New Physics.
Here we present a summary of the theoretical and experimental status of the
search for charged lepton flavor violation in heavy particle decays, in
particular in the decays of the Z and Higgs bosons, and of the top quark.
Decays of beyond-Standard-Model particles such as a Z' or an additional scalar
particle are also discussed. Finally the prospects for such searches at
proposed future electron-positron colliders are reviewed.
