Dorothy uses computer vision and augmented reality to guide, monitor and assist those with dementia. Dorothy transforms a standard walker and tablet computer into an augmented reality-based navigation assistant and remote biosensor allowing family to monitor and assist their relative. Uniquely, Dorothy works independently and deploys rapidly, allowing new care options while supporting COVID-19 distancing. Dorothy is, unlike wearables, accepted by dementia patients and encourages autonomy, with some users navigating independently for the first time. Our mix of common hardware and unique implementation allows anyone to provide care and, in the future, help them isolate problems before they happen.