A method for electronically monitoring terrain and man-made feature displacements using ground-based synthetic aperture radar data, the method comprising estimating displacements of targets located in an area of interest that have taken place between at least a first campaign and at least a subsequent campaign by means of a comparison of a first set of SAR image data acquired in the first campaign in the area of interest with a subsequent set of GBSAR image data acquired in the subsequent campaign in the area of interest, said SAR image data originating from complex SAR images respectively obtained in said campaigns by means of a GBSAR instrument placed in a position in accordance with sensor parameters comprising the position and the orientation of the GBSAR instrument and illuminating said area of interest and a plurality of targets present in said area of interest, the method comprises subjecting a first set of quality-proofed complex SAR images originating from a first set of complex SAR images acquired in said first campaign, to data pre-processing by incoherent temporal averaging to obtain a first incoherent mean SAR image, and subjecting a second set of quality-proofed complex SAR images originating from a second set of complex SAR images acquired in said subsequent campaign, to data pre-processing by incoherent temporal averaging to obtain a second incoherent mean SAR image, whereby the first and second set of quality-proofed complex SAR images are obtained by subjecting each complex SAR image to a quality check and discarding images with problems; selecting, in the first incoherent mean SAR image, first pixels which are representative of said targets in said first set of SAR image data acquired in the first campaign, and selecting, in the second incoherent mean SAR image, second pixels which are representative of said targets in said second set of SAR image data acquired in the second campaign, said targets being selected from artificial corner reflectors, if they are deployed, and natural reflectors in the area of interest; performing a global image matching over the selected pixels to obtain a set of pairs of global shifts expressed in pixels and being representative of one image shift needed to match a given pixel of said first SAR image with a homologous pixel of said second SAR image, and selecting a plurality of quality-scored pairs of global shifts among the pairs of global shifts, by applying a matching score that measures the matching quality of the incoherent mean SAR images; characterised by estimating GBSAR repositioning effects due to differences between the position and orientation of the GBSAR instrument in said first campaign and in said second campaign, by obtaining a mask comprising stable-area pixels corresponding to stable areas in the area of interest, computing a subset of global shifts falling in the mask, estimating a co-registration transformation of said subsets of global shifts, and producing a set of co-registration parameters modelling the GBSAR repositioning effects; estimating pairs of displacements for said first and said subsequent campaign by subtracting the GBSAR repositioning effects modelled by the co-registration parameters from the set of pairs of global shifts, thereby obtaining a plurality of pairs of displacements shifts expressed in pixels which are relative displacements with respect to the whole of the stable-area pixels, converting the displacement shifts expressed in pixels into displacements expressed in a displacement unit, and obtaining a set of pairs of estimated displacements defined in an object space by geocoding, involving an image-to-object transformation.