  In the Standard Model (and MSSM), renormalization effects on neutrino mixing
are generally very small and the attractive fixed points are at vanishing
neutrino mixing. However for multi-higgs extensions of the Standard Model,
renormalization effects on neutrino mixing can be large and nontrivial fixed
points are possible. Here we examine a simple two-higgs model. For two flavors,
maximal mixing is an attractive infrared fixed point. For three flavors, the
neutrino mass matrix evolves towards large off-diagonal elements at low
energies. The experimentally suggested bimaximal neutrino mixing pattern is one
possible attractive infrared fixed point.
