Existing and future facilities of large intensity protons wish to produce neutrino beams for important measurements such as neutrino oscillations or the ultimate test of measuring neutrino species mixing angles and search for CP violation. Although this wishful desire has well placed physics interest at heart, they are neglecting the fact that our knowledge of the neutrino source and background neutrino cross-sections/interaction-specifics rests upon ancient data of bubble chamber experiments. Like the fact that the 40 year old value for the Vus parameter in the CKM matrix was dramatically changed in 2004 by 7 sigma, so too could many of these out of date values change similarly. Experiments like the P960 MIPP upgrade and Minerva experiment at Fermilab would address this important need. This talk will review the need for these improved measurements, and put into context this need to make the current and future neutrino facilities truly valuable for future physics.