In wildland fire management, reliable fire intelligence is needed to direct suppression resources, maintain firefighter safety, predict fire behavior, mitigate fire effects in the environment, and justify and evaluate the effectiveness of fuel management. Fire intelligence needs to be synoptic, quantitative, consistent, and timely. Airborne remote sensing with specialized infrared radiometers is now providing an unprecedented level of information on fire behavior and effects. The temperature, radiant intensity, carbon and sensible heat fluxes, and fuel consumption associated with the flaming front of a wildland fire have been estimated by remotely measuring its radiance at short- and mid-wave infrared wavelengths. Measurements of upwelling longwave or thermal-infrared radiation provide estimates primarily of ground-surface temperatures, even beneath flaming fronts, that reflect a local time course of energy release and fuel consumption. Characteristics of flames and hot ground can be discriminated from radiances measured at wavelengths near 1.6, 3.9, and 11.9 mm. Fire radiance at 3.9 mm appears to be a good estimator of radiant-flux density, which integrates across wavelengths. There are strong temperature gradients along and within flaming fronts, and although their temperatures are high-commonly exceeding 10001C along the line of a savanna fire, for instance-flames may not be bright when compared with a blackbody radiator. The combination of that low bulk emissivity and uncertainty as to the composition and radiance of nonfire background within the sensor's instantaneous field of view dictates that fire properties are best estimated from measurements of high spatial resolution in comparison with the scale of a fire front. The USDA Forest Service is now applying a FireMapper (TM) thermalimaging radiometer for fire research and support of incident command teams over high-priority wildland fires, especially those threatening cities and communities in southern California. Resulting data are providing insight into fire behavior in complex and changing fuels, fire interactions with the atmosphere and a changing climate, and large-scale fire processes.