Interpreting hints for lepton flavor universality violation

We interpret the recent hints for lepton flavor universality violation in rare B meson decays. Based on a model-independent effective Hamiltonian approach, we determine regions of new physics parameter space that give a good description of the experimental data on R-K and R-K*, which is in tension with Standard Model predictions. We suggest further measurements that can help narrowing down viable new physics explanations. We stress that the measured values of R-K and R-K* are fully compatible with new physics explanations of other anomalies in rare B meson decays based on the b -> s mu mu transition. If the hints for lepton flavor universality violation are the first signs of new physics, perturbative unitarity implies new phenomena below a scale of similar to 100 TeV.