First implications of LHCb data on models beyond the Standard Model

We discuss the theoretical and experimental details of two of the main results obtained by LHCb with the 2011 data, namely the measurement of the mixing-induced CP-violation in the decay B_s -> J/psi phi and the upper limits on the decays B_(s) -> mu+ mu-. Then we describe the possible strategies to obtain new constraints on two different New Physics models in the light of these results.