The severity and extent of wildfires in recent years have increased public awareness of a widespread fuels problem in the nation's wildlands. Federal land management agencies have responded with plans to greatly expand fuel treatment programs. However, scant information exists on fuel treatment efficacy for reducing wildfire severity. We investigated the severity of four recent wildfires that burned into existing fuel treatment areas. Treatments included repeated prescribed fires, single prescribed fires, debris removal, and mechanical thinning both with and without slash removal. All treatments were accomplished less than 10 years prior to wildfire occurrence. The historic fire regime of all sampled ecosystems was of the short fire return interval type and included Mississippi slash pine, California Douglas-fir, and ponderosa pine in Colorado and New Mexico. Crown fire hazard (height to crown, crown bulk density, stand density, and basal area), fire resistance (height and diameter), and fire severity (scorch height, crown volume scorch, stand damage, and depth of ground char) were compared between treated and untreated areas. Our results unanimously indicate that treated stands experience lower fire severity than untreated stands that burn under similar weather and topographic conditions. Correlations between fire severity indicators and measures of crown fire hazard and fire resistance were generally good, but individual sites provide unique lessons that illustrate the importance of treating fuel profiles in their entirety. The 20th Century has demonstrated clearly the futility of attempts to eliminate fire from natural landscapes. Society must learn to live with fire and the detente must be realized through the medium of fuel treatments. Both the small percentage of wildfires that encounter fuel treatments and the small scale of treatments within the wildfires we investigated suggest the enormity of the task at hand.