The news is replete with accounts of wildfires burning homes, killing vegetation, disrupting wildlife, or polluting the air or water. Wildfire is at its core a natural phenomenon that most of the world’s terrestrial ecosystems have experienced for millennia. Adequate vegetation cover, occasional dry periods, and a source of ignition are the recipe for fires to start and carry across the landscape. Fires are often part of a natural process of renewal that can help to maintain healthy ecosystems. Alternatively, ecosystems damaged by fire can be susceptible to invasive species, severe erosion, or other disturbances. Vegetation fires currently release carbon equivalent to 20 to 30 percent of annual global fossil fuel emissions. Historically, patterns of fire have changed over time with climate, vegetation changes, and human impacts. Modelers predict that the extent and severity of wildfires could increase in some regions and decrease in others as climate changes. Understanding the balance between fire emissions, carbon uptake by regrowing vegetation, and other ecosystem processes is critical for predicting the effects of such changes. This symposium will address the scientific basis for understanding and predicting fire and its effects. Where and how does fire burn? How does fire affect ecosystems, the environment, and society? How does fire interact with changing climate? How does our knowledge of past fire patterns help us predict the role and impacts of fire in a changing environment?