We report on a two-step process for the fabrication of nanoporous nanowires. The fabrication process involves electrochemical deposition of a single-phase binary alloy into a nanoporous template, followed by subsequent etching of the less noble component. These particles are characterized by diameters of 20 nm or larger, lengths of up to tens of microns, and a porous structure with controlled pore dimensions. In contrast to conventional solid nanoparticles, nonporous nanowires have a high surface area and a well-defined pore morphology. Furthermore, nanoporous segments can be incorporated into multisegment nanorods or nanowires. Here, we demonstrate the fabrication of nanoporous gold (NPG) nanowires and multisegment nanowires incorporating Au/NPG layers and Pt/NPG layers.