Neutrino masses and the next energy scale

We argue that the dominant contribution to the neutrino masses would be provided by those interactions which incorporate a full quark-lepton correspondence and whose characteristic mass scale furnishes the lightest oasis in the so-called energy desert. In particular we discuss the possibility that the suppression of the neutrino mass spectrum has its origin beyond the single-generation level. This allows us, using the minimal U'(1) horizontal symmetry, to correlate the structure of the Majorana mass matrix with the various Dirac mass matrices of the theory. (orig.)