  We discuss several manifestations of charged lepton flavour violation at high
energies. Focusing on a supersymmetric type I seesaw, considering constrained
and semi-constrained supersymmetry breaking scenarios, we analyse different
observables, both at the LHC and at a future Linear Collider. We further
discuss how the synergy between low- and high-energy observables can shed some
light on the underlying mechanism of lepton flavour violation.
