As presented by Bulent Ozbas, Christopher D. O'Neill, Richard A. Register, Ilhan A. Aksay, Robert K. Prud'homme, and Douglas H. Adamson on page 910, the cover image presents functional graphene sheets (FSGs) in a natural rubber matrix. FGSs are shown to be multifunctional nano-fillers for several types of elastomers. FGSs simultaneously improve mechanical properties, reduce gas permeation, and impart electrical conductivity. This combination of property improvements is unavailable in any other filler, including carbon black and nanoclay. The improvements in mechanical properties are shown to be due to the unique shape of FGSs, with their high aspect ratio and crumpled morphology.