After the 1999 storms in France, IFN has considered using satellite imagery to map the damages caused to forests. After a first disappointing urgency test using winter images, IFN gave up this solution and ordered aerial coverages. Two years later, IFN, Cemagref and CESBIO decided to re-explore the use of optical and radar satellite imagery. They developed and validated methods on several test sites representative of french forest conditions in lowland and hill situations. The mapping of the damages with optical was based on a change detection method and carried out in three steps, a pixel-based supervised classification of difference-images, a segmentation of pre-storm images in homogenous objects, and an integration of the pixel-based classification and the segmentation to produce the final damage map. The positive results obtainrd with SPOT summer data allow to envisage operational applications of these methods.