Neutrino interactions: Does nuclear effects and cross-sections understanding really matter in the present/next generation nu-oscillation experiments?

The discovery of the neutrino non-standard properties (mass and mix- ing) refocused on various aspects of the neutrino standard properties, both from the theoretical and the experimental side. In particular, precise mea- surements and modeling of the ν-Nucleus Cross-Section in the intermediate energy range (∼ 0.5–5 GeV), and related Nuclear Effects, are now consid- ered as fundamental issues. In fact, these become necessary for a more robust control of the systematic uncertainties relevant in the forthcoming experimental effort aiming at precision measurements of the MNSP matrix elements. A critical review of the present knowledge motivated the origin and the activity of a wide community progressively formed around these issues. In this introductory review we provide with a qualitative summary of the achievements from the current activity in this field.