Guido, a smart walker developed by Haptica (Dublin, Ireland), is a robotic walking aid that addresses the needs of the frail visually impaired, providing them with a safe means of taking exercise independently as well as navigation assistance in new environments. It was based on a program of research in the Trinity College Dublin from 1995 to 2000. Many similar devices have subsequently been developed, such as the RT-Walker from Kosuge and Hirata Laboratory, the walker developed by Medical Automation Research Center, and the Personal Aid for Mobility and Monitoring (PAMM) devices developed at the Massachusetts Institute of Technology (MIT). Guido has important distinctive characteristics such as its design, its commercialization, and its recently developed map-based navigation. Following the success with the sales of preproduction units of Guido to the U.S. Department of Veterans Affairs, it was withdrawn from the market in early 2002 following the aftereffects of 9/11 and the dot-com crash. Recently, we have initiated a program of research to update Guido, with the latest research results in simultaneous localization and mapping (SLAM). In this article, we review the design and development of Guido and go on to describe the updates that have been empirically evaluated in office and nursing home environments and compare then with the previous control strategy. Finally, the implications are discussed and its future work outlined.