New Physics Interpretations of the B-->K*mu+mu- Anomaly

This talk discusses possible new physics interpretations of recent experimental results on the B-->K*mu+mu- decay that show a discrepancy with the Standard Model predictions. A model independent analysis that takes into account all the relevant observables in B-->K*mu+mu- and in related b-->s transitions allows to identify a consistent new physics explanation of the discrepancy. An explicit realization in the context of a Z' model is presented. The model is based on the U(1) gauge group associated with the difference between muon- and tau-lepton number, L_mu - L_tau.