The increased intensity of wildfires in the American West has halted the progress made in improving air quality. For example, surface ozone and PM2.5 decreased for many years across the West, but these trends have stopped or have even reversed. Another major emerging issue is the occurrence of urban fires as happened in Colorado (Marshall Fire), Hawaii (Lahaina Fire) and California () in just the last few years. In my presentation, I will summarize our group’s work on wildfires. We made measurements of air pollutants after the Marshall Fire both inside smoke-impacted homes as well as outside from a mobile laboratory. One issue with urban fires is that the burnt structures contain many man-made materials. We have studied the emissions from the burning of such materials in the lab, and used the results in the interpretation of our field measurements. Finally, I will discuss how satellite data hold information on the phase of a wildfire (flaming vs. smoldering) and how this information can be used in improved ozone forecasts.