Neutrino mass and grand unification

Simple grand unified theories (GUT) of matter and forces provide a natural home for the seesaw paradigm for understanding small neutrino masses within a framework that also connects quark flavor to that of leptons. This provides a promising possibility for a unified approach to the flavor puzzle. To see what recent indications of a "large" value for the neutrino mixing parameter θ 13 mean for this approach, I report on investigations based on supersymmetric SO(10) GUTs with type II seesaw for neutrino masses and find that it seem to support this point of view, with other predictions testable in near future.