Fermion masses and mixing and CP-violation in SO(10) models with family symmetries

Several ideas for solving the problem of fermion mass hierarchy and mixing and specific supersymmetric models that realize it are reviewed. In particular, we discuss many models based on SO(10) in four dimensions combined with a family symmetry to accommodate fermion mass hierarchy and mixing, including the case of neutrinos. These models axe compared and various tests that can be used to distinguish these models are suggested. We also include a discussion of a few SO(10) models in higher space-time dimensions.