Indium tin oxide (ITO) is the most widely used transparent electrode material today. Although the material possesses a superior combination of high optical transparency and large conductance, conventional ITO thin-film deposition techniques are incompatible with the mechanical and thermal requirements associated with the emerging class of flexible electronic devices. To address this issue, the status of the development of ITO nanostructures such as nanowires and nanoparticles will be reviewed in this article. Two major achievements to be discussed are the growth of vertically oriented arrays of ITO nanowires and the synthesis of small diameter, monodisperse ITO nanoparticles. In addition, solutions of these materials can be deposited utilizing existing printed electronics manufacturing techniques to realize highly transparent, conductive, and flexible ITO thin films on a diverse range of substrates, including plastics. These nanomaterial-based approaches could one day help realize low-cost, flexible electronics based on transparent thin-film electrodes.