A new synthetic aperture radar (SAR) image change detection algorithm was developed using a spatially chaotic model for coherent SAR images. This algorithm is tolerant of misregistration even when the signal-to-noise ratio is low. Despeckling is unnecessary, making the method especially attractive wherever the radiometric changes are subtle. To demonstrate the algorithm's performance, a varied set of multitemporal polarimetric SAR images was used for testing. As a reference, the simple image difference (DI) technique and the principal-component analysis (PCA) were used for comparison. The proposed method performs very well and can detect minute changes despite the presence of speckle, for which both DI and PCA fail.