Anomalies in (semi)leptonic $B$-meson decays present interesting patterns
that might be revealing the shape of the new physics to come. I will
review the decays and observables where these appear, discussing the extent
up to which the respective standard model predictions are understood, especially regarding the
contributions from hadronic matrix elements. In this sense,
the most interesting anomalies are the violation of lepton universality
suggested by a recent measurement of a deficit of $B^+\to K^+\mu\mu$ over
$B^+\to K^+ee$ decays or of surplus of $B\to D^{(*)}\tau \nu$ over $B\to D^{(*)}\ell \nu$. This raises very
interesting questions concerning the lepton-flavor structure of the presumed new
interactions, some of which I will address in the context of effective operators. Finally,
I will discuss new possible experiments that could unambiguously confirm and characterize
the putative new-physics effect.