A method for preparing chemically sensitizod, dislocation-free, silver bromide single crystals is described in this paper. When these crystals are strained beyond the elastic limit and exposed to light, both the dislocation loops which are generated at the surfaces, and the surface terraces which may be associated with them, are made visible by the separation of particles of silver. The glide planes of the dislocations may then be determined from microscopic measurements and the Burgers vectors of the dislocations may be inforred, if the stress distribution responsible for the deformation is at least qualitatively known. This provides a powerful method for studying dislocation interactions and the fundamental processes of plastic deformation.