Abstract
A review is given of elastic spin-polarised low-energy electron diffraction (SPLEED) from crystalline surfaces. For the two relevant spin-dependent interaction mechanisms, spin-orbit coupling, and exchange, dynamical theories are presented with emphasis on symmetry principles, potential models and multiple scattering formalisms. Brief accounts of computational aspects and experimental apparatus (polarised-electron source, spin detectors) are followed by a survey and discussion of experimental and theoretical results for non-magnetic and magnetic surfaces. Finally, the impact of SPLEED on electron emission methods is pointed out, and the prospects of SPLEED as a powerful tool for surface analysis are assessed.