  Rare decays of heavy-flavoured particles provide an ideal laboratory to look
for deviations from the Standard Model, and explore energy regimes beyond the
LHC reach. Decays proceeding via electroweak penguin diagrams are excellent
probes to search for New Physics, and $b \to s \ell^{+}\ell^{-}$ processes are
particularly interesting since they give access to many observables such as
branching fractions, asymmetries and angular observables. Recent results from
the LHCb experiment are reviewed.
