Quark-Lepton Masses and the Neutrino Puzzle in the AGUT Model

We first discuss an approach to the fermion mass problem, according to which the whole of flavour mixing for quarks is determined by the mechanism responsible for generating the physical masses of the up and down quarks: the Lightest Flavour Mass Generation model. Then we consider fermion masses in the Anti-grand Unification Theory and, in particular, the neutrino mass and mixing problem.