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Land degradation monitoring systems must take into account several indicators like vegetation cover, rain-use efficiency, surface run-off, soil erosion. Some of theses indicators may be derived from remote-sensing data. Estimation of vegetation cover from satellite-data relies mainly on conventional or improved vegetation indices, although there is evidence that better results in arid zones have been obtained from the use of spectral unmixing techniques. Estimation of vegetation condition is generally achieved through drought-related indices, obtained from a combination of NIR and SWIR data (canopy water content) or from a combination of NDVI and thermal data (health condition, dryness). NOAA-AVHRR archive data remain the reference data source for identifying temporal trends, but recently available satellite data (EOS-MODIS, MSG-SEVIRI) should give significantly improved monitoring results due to better spectral, spatial or temporal resolutions.