  The implementation of maximally restrictive texture zeros in the leptonic
sector is investigated in the context of two-Higgs-doublet models with Majorana
neutrinos. After analyzing all maximally restrictive pairs of leptonic mass
matrices with zero entries, we conclude that there are only four texture
combinations that are compatible with observations at 3 sigma confidence level
and can be implemented through Abelian symmetries in a two-Higgs-doublet model.
The compatibility of these textures with current constraints on
lepton-flavor-violating processes is also studied. The ultraviolet completion
of these models is discussed in the framework of the seesaw mechanism for
neutrino masses.
