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In multilayers, the magnitude of exchange bias, can be considerably enhanced by placing an ultrathin nonmagnetic Pt spacer between the multilayer (ML) and the antiferromagnetic (AFM) layer. The bias is maximum for a spacer layer thickness, of a few angstroms and it decreases progressively as is further increased. This bias enhancement is accompanied by an increase of coercivity, This behavior is due to the role of the Pt spacer in enhancing the perpendicular effective anisotropy of the last Co layer in the ML, which has the effect of increasing the net ferromagnetic (FM)/AFM spin projection, thus leading to the and enhancements. The decrease of and for thicker spacer layers is due to the limited range of the FM–AFM proximity effect.