2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/163679In this contribution we describe a new model of multiple partonic interactions that has been implemented in Herwig++. Tuning its two free parameters we find a good description of CDF underlying event data. We show extrapolations to the LHC and discuss intrinsic PDF uncertainties.4 pages, 2 figures, to appear in the proceedings of the DIS 2008 workshop, 7-11 April 2008, University College LondonHigh Energy Physics - Phenomenologytext