Democratic approach to atmospheric and solar neutrino oscillations

Working with a <f>U(1)</f> flavor symmetry, we show how the hierarchical structure in the charged fermion sector and a democratic approach for neutrinos that yields large solar and atmospheric neutrino mixings can be simultaneously realized in the MSSM framework. However, in <f>SU(5)</f> due to the unified multiplets we encounter difficulties. Namely, democracy for the neutrinos leads to a wrong hierarchical pattern for charged fermion masses and mixings. We discuss how this is overcome in flipped <f>SU(5)</f>. [Copyright &y& Elsevier]