This dissertation uses quantitative analysis to provide insights for the urban and transportation policy-making process in order to manage two transportation externalities: road safety and air pollution in Bogotá Colombia. I performed a safety transportation risk analysis, which shows a high fatality and injury risk from road crashes in Bogota. I then analyzed safety-related benefits and costs of crash avoidance technology used in transit buses. My analysis reveals that despite of the life-safety benefit expected, Bogota’s values of statistical life and injuries make an investment on the technology for buses fall into the economically unjustified ranges. To analyze traffic related air pollution emissions, I developed a link-based emission model, which then it’s used to explore the traffic-related air pollution impacts of a highway capacity enhancement plan and a scrappage program for private cars. I use a bottom-up model that couples detailed activity data from a TAM, developed in EMME/4, with various emissions factors to develop a high-resolution road traffic emissions inventory for Bogotá. In particular, I use three emission models to produce the traffic related emission inventory, which includes exhaust emissions of five criteria air pollutants: Carbon monoxide (CO), Nitrogen Oxide (NOx), Sulphur oxides (SO2), Particulate Matter (PM, particles with diameters of 10 micrometers and smaller), and Volatile Organic Compound (VOC) emissions generated by hot-stabilized vehicle activity. The on-road vehicle emission model developed as part of this work marks an important turn over previous tools, because it opens the possibility to integrate environmental and transportation policy-making in Bogota. Integrating transportation and environmental policies has the potential to move the focus of environmental programs from “end-of-the-pipe” solutions to holistic analysis of how the land use, transportation systems and vehicle technology decisions play out on the levels of pollution in the city.