Emissions of air pollutants by mobile sources are responsible for more than 60% of total air pollution. One of the main sources is vehicle exhaust emissions. Researchers analyze vehicle emissions using remote sensing technology. Researchers are responsible for conducting the Continuous Atlanta Fleet Evaluation (CAFÉ) program for the Georgia Department of Natural Resources. CAFÉ is the longest-running remote sensing program in the world. Collected emissions data is evaluated biannually to assess the effectiveness of Atlanta’s Inspection and Maintenance program.