This paper considers the difficulties encountered in conventional thin-foi1 electron microscopy of alkali halides and demonstrates how each can - within certain limits - be successfully overcome. The measures required include careful thin-foi1 specimen preparation and examination at liquid helium temperature. In particular, low temperature microscopy is shown to significantly retard the onset of observable radiation damage effects induced by the investigating electron beam. A brief account of the application of these techniques to studies of irradiation defect aggregations and dislocation behaviour in irradiated and deformed alkali halide crystals is presented