  The ALICE Collaboration has studied inclusive J/$\psi$ and $\psi$(2S)
production in p-Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV with the Muon
Spectrometer. The measurement was performed at forward (2.03 $<$ $y_{\rm cms}$
$<$ 3.53) and backward ($-$4.46 $<$ $y_{\rm cms}$ $<$ $-$2.96) centre of mass
rapidities. The nuclear modification factor of J/$\psi$ and $\psi$(2S) has been
measured as a function of transverse momentum and event activity. Theoretical
models based on nuclear shadowing, coherent energy loss or both are in
reasonable agreement with the J/$\psi$ results but cannot describe the
$\psi$(2S) behaviour. Other mechanisms must be invoked in order to explain the
$\psi$(2S) suppression in p-Pb collisions.
