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Forest fires play a dominant role in Spanish landscapes. During the last three decades, there were over 14,000 fires per year, which swept through ca. 200,000 ha. These fires burned a total of nearly 6 Mha, of a forested area of ca. 25 Mha. Fires occurred virtually everywhere throughout the country, except in the valleys of the large rivers, where agriculture landscapes dominate (Moreno et al., 1998)(Figure 1). Fire incidence, however, varied greatly between regions. Particularly “hot” areas were the North-west (the region of Galicia), and the mountains along the Mediterranean Sea, of the Central System, and of the southern ranges. Based on data from the last decade, most fires are caused by people (Vázquez & Moreno, 1998)(97%), lightning causing only 3%. Of the human-induced fires, the majority of them were lit intentionally (ca. 60%). Negligence and other accidental causes accounted for less than 20% of all fires, and the rest were caused by unknown sources. Climate is a major determinant of the occurrence of forest fires and of fire regime across the globe. Climate determines the vegetation of any given place, its primary productivity and, in combination with physiographic features, the land-use of the area, which affects the type of human-influenced vegetation apt to burn. For a fire to ignite and spread, the appropriate conditions are critical. These include, high temperatures and low air relative humidity, dry soils and litter, and wind. In Spain, where most of the country has a Mediterranean-type climate, the summer months are particularly critical. This is reflected in the high values of some fire danger indices used by the forest services to alert …