  We review flavour and CP violations in the lepton sector as probes of new
physics beyond the standard model and its minimal extensions accommodating
massive neutrinos. After recalling the main experimental bounds and the future
perspectives, we summarize the limits on a set of dimension-six gauge-invariant
operators, pointing to a scale of new physics much larger than the electroweak
scale. If we insist on having new physics at the TeV scale, as demanded by most
of the standard model extensions addressing the gauge hierarchy problem, we
should rely on special mechanisms to deplete flavour and CP violations in the
charged lepton sector. We comment on the capability of partial compositeness in
reconciling the absence of signals with a scale of new physics accessible to
the LHC.
