  In the absence of a fundamental principle preventing charged lepton flavour
violation, one expects that extensions of the Standard Model accommodating
neutrino masses and mixings should also allow for charged lepton flavour
violating processes such as $\ell_i \to \ell_j\gamma$, $\ell_i \to \ell_j
\ell_k \ell_m $ and $\mu - e$ conversion in nuclei, for which the rates depend
in general on the mechanism of neutrino mass generation. In addition to
low-energy experiments, there are also searches for lepton flavour violation at
colliders, where new physics can be directly probed through flavour violating
production and/or decays of heavy states. In a model independent way, we
briefly use effective operators responsible for these processes to derive
information about the underlying framework of new physics. We then consider
some specific classes of models (supersymmetry, extra dimensions, grand unified
theories) that account for rich scenarios of charged lepton flavour violation.
We also comment on the r\^ole of charged lepton flavour violation in
disentangling models of new physics.
