During the last ten years, a lot of experimental information has been collected from neutrino oscillation experiments on the masses and and mixings among the three known neutrino species. This presents an almost comparable flavor picture for leptons as is already known to exist for quarks. In the talk I would like to discuss what these results imply for physics beyond the standard model since SM predicts zero neutrino mass. In particular, it seems that one can make a compelling case for the idea of grand unified theory of matter and forces as a candidate theory for neutrinos as well as providing a possible route to flavor unification. I will outline these arguments, present a candidate theory and discuss its tests.