The talk summarizes the CMS Underlying Event studies in pp interactions up to highest centre of mass energies of 7 TeV. The Underlying Event in Drell-Yan and jet events is studied measuring the charged multiplicity and energy densities in different regions, defined considering the azimuthal distance of the reconstructed tracks, with respect to the reconstructed boson and leading track-jet. Complementary measurements in the forward region and a methodology using the jet median/area approach are discussed.
We compare our underlying event results with the predictions from different Monte Carlo generators and tunes. We also review the implications of the soft QCD Multiple Parton Interactions measurements on the descriptions of some rare Standard Model events characterized by two or more hard parton scatterings discussing the forthcoming measurements in this field.