Engineered surfaces are essential in fuel cells, where the external surface properties and the pore structure affect performance. The hydrogen used as the fuel in fuel cells may be generated from hydrocarbons by catalytic reforming, usually in a reactor module associated directly with the fuel cell. The potential use of nano-engineered membranes to intensify catalytic processes could enable higher-efficiency, small-scale fuel cells. These could act as distributed sources of electrical power. It may eventually be possible to produce hydrogen locally from sources other than hydrocarbons, which are the feedstocks of current attention. For hydrogen storage applications, metal nanoclusters appear to have many potential applications. Metal nanoclusters have also been utilized as catalytic centers for the growth of single walled carbon nanotubes, which are being investigated as hydrogen storage devices.