Devices which provide electronic vision enhancement have many potential advantages over optical aids, when used to avoid the activity limitation caused by visual impairment. They can provide an extremely high level of magnification over a field of view which is not aberration-limited, and the image can be viewed binocularly from a comfortable working distance. In addition to magnification, the image can be manipulated to introduce artificial colour, contrast reversal or enhancement, and text can be reformatted. This review updates the classification of electronic vision enhancement devices designed specifically for the visually impaired, explaining the characteristics of current electronic vision enhancement systems (EVES). Examples are given of the most common devices, and their potential usage, along with information about some companies currently supplying EVES to users in the UK, and the services they offer.