Because of their shape anisotropy, nanorods are attractive components for creating functional polymer nanocomposites. In many cases, this anisotropy is the basis of physical properties that are distinct from those obtained from isotropic particles, such as nanospheres. For instance, the shape of gold nanorods makes them ideal candidates for applications involving the manipulation of incident light and sensitive molecular spectroscopy due to enhanced polarizability of the particle. On the other hand, semiconducting nanorods, such as those composed of CdSe, have shown promise in polymer-based photovoltaic devices as sites for electron transport and charge transfer. In this Perspective, we motivate the fabrication of functional polymer nanocomposites based specifically upon the inclusion of nanorods over other nanoparticle shapes and discuss ways in which the anisotropy of the individual nanoparticles enhances assembly in and the properties of polymer nanocomposites in comparison to spherical nanoparticles. We briefly summarize methods to successfully disperse and organize nanorods within polymers and discuss applications of polymer nanocomposites involving sensing, energy harnessing, and mechanical enhancement. Finally, we comment on unresolved issues for fabricating nanorod-based polymer composites and suggest topics warranting future investigation.