  We briefly discuss the present status of models of neutrino mixing. Among the
existing viable options we review the virtues of Bimaximal Mixing (that could
be implemented by an $S_4$ discrete symmetry), corrected by terms arising from
the charged lepton mass diagonalization. In particular in a GUT formulation the
property of quark lepton "weak" complementarity can be naturally realized. We
discuss in some detail two new versions of particular GUT models, one based on
$SU(5)$ and one on $SO(10)$ and the associated phenomenology. We compare these
approaches based on symmetry to models based on chance, like Anarchy or
$U(1)_{FN}$.
