There is clear demand for a global spatial public domain roads data set with improved geographic and temporal coverage, consistent coding of road types, and clear documentation of sources. The currently best available global public domain product covers only one-quarter to one-third of the existing road networks, and this varies considerably by region. Applications for such a data set span multiple sectors and would be particularly valuable for the international economic development, disaster relief, and biodiversity conservation communities, not to mention national and regional agencies and organizations around the world. The building blocks for such a global product are available for many countries and regions, yet thus far there has been neither strategy nor leadership for developing it. This paper evaluates the best available public domain and commercial data sets, assesses the gaps in global coverage, and proposes a number of strategies for filling them. It also identifies stakeh...