The first part of my talk I will discuss models where the SM fermion mass hierarchy is generated by a sequential loop suppression mechanism. These models have viable dark matter candidates. In the second part of my talk I will explain how the Universal and inverse seesaw mechanisms can be implemented in a Pati-Salam and in the left-right symmetric model with a Delta(27) family symmetry to get viable and predictive textures for the fermion sector. In the third part of my talk I will discuss a SU(3)CxSU(3)LxU(1)X model where the pattern of SM fermion masses and mixings arises from the spontaneous breaking of the discrete symmetries and the light neutrino masses are generated by a low scale seesaw mechanism.