[en] The need for polarized beams at hadron-hadron colliders is reviewed. As an example, lowest order Drell-Yan is examined at the resonance for a new scalar or vector boson. Assuming only scalar and pseudoscalar couplings in the case of a spin zero boson or vector and pseudovector couplings for a new vector boson, it is clear that polarization is required if complete information on the interactions is desired from hadron-hadron collisions. For this case, a study with one beam carrying longitudinal polarization combined with a study where both beams have a transverse polarization is required