"Wildland fire suppression operations successfully control ninety-seven to ninety-nine percent of all wildfires at initial attack, and structure firefighters typically limit a fire within a single structure or prevent the fire from spreading beyond that structure. However, when residential development is exposed to extreme wildfire conditions, numerous houses can ignite and burn simultaneously, overwhelming firefighters and reducing fire protection effectiveness. Thus, WUI fire disasters principally occur during the extreme fire behavior conditions that account for the one to three percent of the wildfires that escape initial attack control. Table 1 lists WUI fire disasters between 1990 and 2007. Every one of these disasters occurred because extreme fire behavior conditions overwhelmed the firefighting resources."