We present a quantitative kinematic model of thrust evolution that allows detailed interpretation of the stratigraphic record of foreland basins. Simulation of thrusting and syntectonic sedimentation shows that changes in the relative rate of thrusting and mode of thrust activation can be determined by their expression in basin stratigraphy. Truncations and offlaps reflect thrust activity, and hinterland migration of basin depocenters indicates out-of-sequence thrusting. Forward modeling of the stratigraphic record of the Pliocene-Quaternary Po basin, Italy, enables the quantitative reconstruction of the displacement sequence of the thrust sheets prograding into the basin during the Pliocene. Deep-seated middle Pliocene thrusting accompanied by out-of-sequence thrusting provides a consistent explanation for the observed stratigraphic record of the Po piggyback basins.