  The determination of the differential branching fraction and the first
angular analysis of the decay $B_s^0\to\phi\mu^{+}\mu^{-}$ are presented using
data, corresponding to an integrated luminosity of $1.0\,{\rm fb}^{-1}$,
collected by the LHCb experiment at $\sqrt{s}=7\,{\rm TeV}$. The differential
branching fraction is determined in bins of $q^{2}$, the invariant dimuon mass
squared. Integration over the full $q^{2}$ range yields a total branching
fraction of ${\cal B}(B_s^0\to\phi\mu^{+}\mu^{-}) = (7.07\,^{+0.64}_{-0.59}\pm
0.17 \pm 0.71)\times 10^{-7}$, where the first uncertainty is statistical, the
second systematic, and the third originates from the branching fraction of the
normalisation channel. An angular analysis is performed to determine the
angular observables $F_{\rm L}$, $S_3$, $A_6$, and $A_9$. The observables are
consistent with Standard Model expectations.
