New physics in rare decays

After two decades of the great discoveries, neutrino physics is now entering the era of precision measurements with massive detectors. In this talk, I would like to discuss new physics scenarios related to the observations at the next-generation neutrino experiments, in particular, (1) New physics contributions to neutrinoless double beta decay processes, (2) Nucleon decays, to which we can expect the improvement in sensitivity at the massive neutrino detectors, and their relation to neutrino mass models.