GIS, with their predominantly visual communication of spatial information, may appear to have little to offer people with visual impairments or blindness. However, because GIS store and manage the spatial relations between objects, alternative, non-visual ways to communicate this information can be utilized. As such, modified GIS could provide people with visual impairments access to detailed spatial information that would aid spatial learning, orientation, and spatial choice and decision making. In this paper, we explore the ways that GIS have been, and might be, adapted for use by people with visual impairments or blindness. We review current developments, report upon a small experimental study that compares the ability of GIS-based and various adaptive technologies to communicate spatial information using non-visual media, and provide an agenda for future research. We argue that adapted GIS hold much promise for implicitly improving the quality of life for visually impaired people by increasing mobility and independence.