The development of new transportation infrastructure requires a complex set of regulatory approvals, including those regarding potential impacts to at-risk species listed by federal and/or state agencies. Transportation development is more efficient when it is able to avoid negative impacts to at-risk species from the outset of a project. When avoidance is not possible, a comprehensive understanding of mitigation options early in project planning supports project streamlining. All of these planning options require a defensible fine scale understanding of the distribution of species at-risk. However, coarse range maps are the most readily available current information resource on species distributions. The central federal resources for species distributions (i.e. USDA Plants, FWS ECOS) provide distribution information at the level of county boundaries. Presence/absence of a sensitive species in a county is of limited value for the spatially explicit needs of transportation planning. NatureServe and its national network of Natural Heritage Programs have high quality, high precision observation data on at-risk species occurrences in the locations that network biologists have had the opportunity to conduct field surveys. But gaps remain, both due to limited resources for field inventory and issues of access, especially in states with large percentages of private lands. Species distribution modeling (SDM) is an academically mature tool that can provide transportation planners with information about the distribution of suitable habitat for species of concern. SDMs use reliable occurrence records together with digital spatial information on the environment, such as climate, topography, hydrology, and vegetation cover, to project produce maps of the probability of suitable habitat for target species. Recent peer-reviewed publications have established standards for the development and delivery of distribution models to support management decisions, such as those involving sensitive species in transportation projects. In collaboration with Esri, TNC, and Microsoft AI for Earth, NatureServe has begun to develop a national library of at-risk species distribution models for over 2500 species of national conservation concern. Each model contains evaluative criteria for its performance against best-practice standards in SDM. A model review tool has been developed to allow all stakeholders to review and comment on model outputs, facilitating open and transparent translation of model results into final decisions about where at-risk species could occur. These efforts offer a science-based approach to refining at-risk species distributions that could provide significant benefits to the transportation sector, by reducing conflict, reducing duplication of effort, streamlining regulatory decision making, while also increasing the efficiency of conservation investments. In this presentation, we will review the current status and future directions of SDM applied to at-risk species management and conservation, with an emphasis on relevance to the transportation sector. We will review recent development in creating standards for SDM applied to management decisions, and demonstrate tools for insuring transparency and stakeholder participation in refined range mapping.