  The observation of a charged-lepton flavor violating process would be a
definite sign for physics beyond the Standard Model, but would actually only
prove that one particular linear combination of lepton numbers is violated. We
categorize lepton-flavor-violating processes by their quantum numbers and show
how their discovery can be interpreted model independently, studying in
particular which processes are required to establish that the entire flavor
group is broken. We also comment on total lepton number, seeing as lepton
number violation practically implies lepton flavor violation as well.
