Electron and neutrino scattering in the Delta-resonance region and beyond

We present a unified relativistic approach to inclusive electron scattering based on the relativistic Fermi gas model and on a phenomenological extension of it which accounts for the superscaling behaviour of $(e,e')$ data. We present results in the $\Delta$ resonance region and in the highly inelastic domain and show some application to neutrino scattering.