The success of the next generation of neutrino-oscillation experiments requires significant reduction of systematic uncertainties. In this context, the description of nuclear effects in neutrino interactions is of particular importance, as it currently is one of the main systematic effects. Here I discuss the relevance of realistic description of the ground-state properties of the target nucleus, pointing out the importance of developing accurate theoretical models, capable to provide quantitative description of neutrino cross sections, together with the relevance of their implementation in Monte Carlo generators and extensive testing against lepton-scattering data.